=== EXISTING QUESTIONS (from SPL Exam Questions EN) ===

Flight Performance and Planning

Source: QuizVDS.it (EASA ECQB-SPL) | 30 questions Free practice: https://quizvds.it/en-en/quiz/spl-en


Q1: Exceeding the maximum allowed aircraft mass is... ^q1

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q1) - A) Compensated by the pilot's control inputs. - B) Only relevant if the excess is more than 10 %. - C) Exceptionally permissible to avoid delays - D) Not permissible and essentially dangerous Correct: D)

Explanation: The maximum allowable mass (MTOM) is a structural and aerodynamic certification limit, not a guideline. Exceeding it increases wing loading, raises the stall speed, degrades climb performance, and overstresses the airframe — potentially beyond its certified load factors. No pilot input can compensate for a structurally compromised aircraft. There is no regulatory or safety margin that permits any excess, even temporarily.

Q2: The center of gravity has to be located... ^q2

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q2) - A) Behind the rear C.G. limit - B) In front of the front C.G. limit. - C) Right of the lateral C. G. limit. - D) Between the front and the rear C.G. limit. Correct: D)

Explanation: The approved C.G. envelope defines the range within which the aircraft's stability and controllability have been certified. If the C.G. moves forward of the front limit, elevator authority may be insufficient to rotate at takeoff or flare on landing. If it moves aft of the rear limit, the aircraft becomes statically unstable and pitch oscillations can become uncontrollable. The C.G. must remain between both limits throughout the entire flight.

Q3: An aircraft must be loaded and operated in such a way that the center of gravity (CG) stays within the approved limits during all phases of flight. This is done to ensure... ^q3

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q3) - A) That the aircraft does not exceed the maximum permissible airspeed during a descent - B) Both stability and controllability of the aircraft. - C) That the aircraft does not tip over on its tail while it is being loaded. - D) That the aircraft does not stall. Correct: B)

Explanation: The C.G. position relative to the aerodynamic neutral point determines longitudinal static stability. A C.G. forward of the neutral point produces a restoring pitching moment (stability), while control authority provides maneuverability (controllability). If the C.G. is outside limits, one of these two properties is compromised — either the pilot cannot correct a pitch upset, or the aircraft does not naturally resist one. Stall speed and Vne are influenced by other parameters and are not the primary reasons for the C.G. requirement.

Q4: The empty weight and the corresponding center of gravity (CG) of an aircraft are initially determined... ^q4

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q4) - A) By weighing. - B) By calculation. - C) For one aircraft of a type only, since all aircraft of the same type have the same mass and CG position - D) Through data provided by the aircraft manufacturer. Correct: A)

Explanation: Each individual aircraft is physically weighed — typically on three-point scales — to determine its actual empty mass and C.G. position. Manufacturing tolerances, repairs, and installed equipment vary between serial numbers of the same type, so manufacturer tables alone are insufficient. The results are recorded in the aircraft's weight and balance report and must be updated after any modification that changes mass or mass distribution.

Q5: Baggage and cargo must be properly stowed and fastened, otherwise a shift of the cargo may cause... ^q5

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q5) - A) Calculable instability if the C.G. is shifting by less than 10 %. - B) Continuous attitudes which can be corrected by the pilot using the flight controls. - C) Structural damage, angle of attack stability, velocity stability. - D) Uncontrollable attitudes, structural damage, risk of injuries. Correct: D)

Explanation: In turbulence or during aerobatics, unsecured cargo can shift suddenly and move the C.G. outside limits instantaneously — faster than a pilot can react. A sudden aft C.G. shift can cause an unrecoverable pitch-up; items becoming projectiles can injure occupants or jam controls. The structural risk arises from asymmetric loading exceeding design limits. No prior stability analysis can make unsecured cargo acceptable.

Q6: The total weight of an aeroplane is acting vertically through the... ^q6

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q6) - A) Stagnation point. - B) Center of pressure. - C) Neutral point. - D) Center of gravity Correct: D)

Explanation: By definition, the center of gravity (C.G.) is the single point through which the resultant gravitational force (weight vector) acts on the entire aircraft. The center of pressure is where the resultant aerodynamic force acts, the neutral point is the aerodynamic reference for stability analysis, and the stagnation point is where airflow velocity is zero on the leading edge — none of these is where gravity acts.

Q7: The term "center of gravity" is defined as... ^q7

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q7) - A) Another designation for the neutral point. - B) The heaviest point on an aeroplane. - C) Half the distance between the neutral point and the datum line. - D) Half the distance between the neutral point and the datum line. Correct: D)

Explanation: The center of gravity is the point through which the total weight force of the aircraft acts. It is the mass-weighted average position of all individual mass elements of the aircraft. It is not the physically heaviest point, and it is distinct from the neutral point (an aerodynamic concept). All mass and balance calculations reference moments about the datum to locate this point.

Q8: The center of gravity (CG) defines... ^q8

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q8) - A) The product of mass and balance arm - B) The point on the longitudinal axis or its extension from which the centers of gravity of all masses are referenced. - C) The point on the longitudinal axis or its extension from which the centers of gravity of all masses are referenced. - D) The point through which the force of gravity is said to act on a mass. Correct: D)

Explanation: The C.G. is the point through which gravity (weight) is considered to act on the entire aircraft as if all mass were concentrated there. This definition is fundamental to mass and balance calculations: moments of all individual masses are summed and divided by total mass to locate this point. The datum is a fixed reference point, not the C.G. itself, and moment is the product of mass times arm.

Q9: The term "moment" with regard to a mass and balance calculation is referred to as... ^q9

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q9) - A) Sum of a mass and a balance arm. - B) Difference of a mass and a balance arm. - C) Quotient of a mass and a balance arm. - D) Product of a mass and a balance arm. Correct: D)

Explanation: In mass and balance, moment = mass × balance arm (M = m × d), expressed in kg·m or lb·in. This follows the physical definition of a torque or moment of force. The total C.G. position is then found by: C.G. = (sum of all moments) ÷ (total mass). Using a sum, difference, or quotient instead of a product would yield a dimensionally and physically incorrect result.

Q10: The term "balance arm" in the context of a mass and balance calculation defines the... ^q10

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q10) - A) Distance of a mass from the center of gravity - B) Point on the longitudinal axis of an aeroplane or its extension from which the centers of gravity of all masses are referenced. - C) Distance from the datum to the center of gravity of a mass. - D) Point through which the force of gravity is said to act on a mass. Correct: C)

Explanation: The balance arm (or moment arm) is the horizontal distance measured from the aircraft's datum line to the center of gravity of a particular mass item (e.g., pilot, ballast, equipment). It determines the leverage that mass exerts about the datum. Distances from the C.G. itself are not balance arms — the datum is always the reference point. The datum is defined in the aircraft's flight manual and is fixed for that aircraft type.

Q11: The distance between the center of gravity and the datum is called... ^q11

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q11) - A) Lever. - B) Torque. - C) Span width. - D) Balance arm. Correct: D)

Explanation: In mass and balance terminology, the balance arm (also called moment arm) is specifically the horizontal distance from the aircraft datum to any given point of interest — including the overall C.G. once calculated. Torque/moment is the product of mass and arm, not the distance itself. Span width is a geometric wing parameter unrelated to longitudinal mass and balance.

Q12: The balance arm is the horizontal distance between... ^q12

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q12) - A) The C.G. of a mass and the rear C.G. limit. - B) The front C.G. limit and the datum line - C) The front C.G. limit and the rear C.G. limit. - D) The C.G. of a mass and the datum line. Correct: D)

Explanation: The datum is an arbitrary but fixed reference plane (often the firewall, wing leading edge, or nose) defined in the aircraft's flight manual. The balance arm of any mass is measured as the horizontal distance from this datum to the center of gravity of that specific mass. All moment calculations use this datum as the common reference, allowing moments to be summed algebraically to find the total C.G. position.

Q13: The required data for a mass and balance calculation including masses and balance arms can be found in the... ^q13

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q13) - A) Certificate of airworthiness - B) Mass and balance section of the pilot's operating handbook of this particular aircraft. - C) Performance section of the pilot's operating handbook of this particular aircraft. - D) Documentation of the annual inspection. Correct: B)

Explanation: The Pilot's Operating Handbook (POH) or Aircraft Flight Manual (AFM) contains a dedicated mass and balance section with the aircraft's empty mass, empty C.G. position, datum reference, C.G. limits, and approved loading configurations. The certificate of airworthiness merely certifies the aircraft type is approved; the annual inspection records maintenance history. Performance data (speeds, glide ratios) is in a different POH section.

Q14: Which section of the flight manual describes the basic empty mass of an aircraft? ^q14

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q14) - A) Limitations - B) Normal procedures - C) Weight and balance - D) Performance Correct: C)

Explanation: The Weight and Balance section (Section 6 in EASA-standardized AFM/POH structure) contains the aircraft's basic empty mass, empty C.G. location, allowable C.G. range, and loading instructions. The Limitations section covers maximum speeds, load factors, and operating envelope. Normal Procedures covers checklists. Performance covers speeds, climb rates, and glide distances. Each section has a specific regulatory and operational purpose.

Q15: Which factor shortens landing distance? ^q15

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q15) - A) Heavy rain - B) High pressure altitude - C) High density altitude - D) Strong head wind Correct: D)

Explanation: A headwind reduces groundspeed at touchdown for a given airspeed, so the aircraft arrives over the threshold with less kinetic energy to dissipate — shortening the ground roll. As a rule of thumb, a headwind component equal to 10% of approach speed reduces landing distance by approximately 19%. Conversely, high pressure altitude and high density altitude increase true airspeed at a given IAS, increasing groundspeed and lengthening landing distance. Heavy rain can reduce braking effectiveness, further increasing landing distance.

Q16: Unless the aircraft is equipped and certified accordingly... ^q16

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q16) - A) Flight into forecast icing conditions is prohibited. Should the aircraft enter an area of icing conditions inadvertantly, the flight may be continued as long as visual meteorological conditions are maintained. - B) Flight into known or forecast icing conditions is only allowed as long as it is ensured that the aircraft can still be operated without performance degradation. - C) Flight into known or forecast icing conditions is prohibited. Should the aircraft enter an area of icing conditions inadvertantly, it should be left without delay. - D) Flight into areas of precipitation is prohibited. Correct: C)

Explanation: For aircraft not certified for flight into known icing (FIKI), operating in known or forecast icing conditions is a regulatory prohibition, not merely a performance consideration. Ice accretion on a glider's wings dramatically increases weight (shifting the C.G.), increases drag, reduces the maximum lift coefficient, and raises the stall speed — all simultaneously. If inadvertently encountered, the pilot must exit the icing environment immediately by changing altitude or heading, regardless of visual conditions.

Q17: The angle of descent is defined as... ^q17

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q17) - A) The ratio between the change in height and the horizontal distance travelled within the same time, expressed in percent [%]. - B) The angle between a horizontal plane and the actual flight path, expressed in degrees [°]. - C) The angle between a horizontal plane and the actual flight path, expressed in percent [%]. - D) The ratio between the change in height and the horizontal distance distance travelled within the same time, expressed in degrees [°]. Correct: B)

Explanation: The angle of descent (or glide angle) is geometrically defined as the angle between the horizontal and the actual flight path vector, measured in degrees. It is related to — but not the same as — the glide ratio: glide ratio = horizontal distance / height lost = 1/tan(glide angle). A glide ratio of 1:30 corresponds to a glide angle of approximately 1.9°. Expressing it as a percentage would make it a gradient, not an angle.

Q18: What is the purpose of "interception lines" in visual navigation? ^q18

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q18) - A) They are used as easily recognizable guidance upon a possible loss of orientation - B) They help to continue the flight when flight visibility drops below VFR minima - C) To mark the next available en-route airport during the flight - D) To visualize the range limitation from the departure aerodrome Correct: A)

Explanation: Interception lines are prominent, linear geographic features — rivers, coastlines, railways, motorways — selected during pre-flight planning that run roughly perpendicular to the planned route. If a pilot becomes disoriented, flying toward the nearest interception line will produce an unmistakable landmark that allows position recovery. They do not extend permissions below VFR minima and are not range indicators; they are specifically a lost-procedure planning tool.

Q19: The upper limit of LO R 16 equals... ^q19

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q19)

Note: This question originally references a chart excerpt (PFP-056) showing LO R 16 airspace boundaries. - A) 1.500 ft GND. - B) 1 500 ft MSL. - C) 1 500 m MSL. - D) FL150. Correct: B)

Explanation: Low-level restricted areas (LO R) published in national AIPs and on VFR charts typically express their vertical limits in feet MSL (above mean sea level) unless explicitly stated otherwise with GND/AGL. The notation "1 500 ft MSL" means the restriction applies from the surface (or a lower altitude boundary) up to 1,500 feet above mean sea level. Glider pilots must cross-check the AIP ENR section and current NOTAM for activation times and exact limits.

Q20: The upper limit of LO R 4 equals... ^q20

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q20)

Note: This question originally references a chart excerpt (PFP-030) showing LO R 4 airspace boundaries. - A) 1.500 ft AGL - B) 4.500 ft AGL. - C) 4.500 ft MSL - D) 1.500 ft MSL. Correct: C)

Explanation: As with Q19, restricted airspace limits are read directly from the relevant chart or NOTAM. The designation "4 500 ft MSL" indicates the upper vertical boundary is 4,500 feet above mean sea level — higher than a typical low-level restriction, reflecting terrain or operational considerations for that specific area. AGL (above ground level) would imply the limit varies with terrain; MSL is an absolute altitude referenced to a fixed datum.

Q21: Up to which altitude is an overflight prohibited according to the NOTAM? ^q21

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q21)

Note: This question originally references a NOTAM excerpt (PFP-024). - A) Altitude 9500 ft MSL - B) Flight Level 95 - C) Altitude 9500 m MSL - D) Height 9500 ft Correct: A)

Explanation: NOTAM altitude references follow ICAO conventions: "Altitude" refers to height above MSL (mean sea level), "Height" refers to height above a local ground reference, and "Flight Level" is a pressure altitude reference (used above the transition altitude). The NOTAM in question prohibits overflight up to 9,500 ft MSL — a specific absolute altitude. 9,500 m MSL would be approximately 31,000 ft, clearly inconsistent with a typical VFR NOTAM restriction.

Q22: What must be considered for cross-border flights? ^q22

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q22) - A) Transmission of hazard reports - B) Requires flight plans - C) Regular location messages - D) Approved exceptions Correct: B)

Explanation: Under ICAO Annex 2 and national regulations, flight plans are mandatory for international flights crossing state borders, even for VFR glider flights. The flight plan is required for border control coordination, search and rescue alerting, and compliance with customs/immigration procedures. A filed and activated flight plan ensures that the relevant Air Traffic Services units and SAR services are aware of the flight. Hazard reports and location messages are separate AIREP/PIREP procedures.

Q23: During a flight, a flight plan can be filed at the... ^q23

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q23) - A) Search and Rescue Service (SAR). - B) Flight Information Service (FIS). - C) Next airport operator en-route. - D) Aeronautical Information Service (AIS) Correct: B)

Explanation: The Flight Information Service (FIS), reached on the published FIS frequency in each FIR, can accept an airborne flight plan (AFIL) during flight. This is the standard procedure when a flight plan was not filed before departure or when an extension is needed. SAR is a response service, not a flight planning authority. AIS distributes aeronautical information but does not accept real-time flight plans. Airport operators handle local arrivals and departures, not en-route plan filing.

Q24: While planning a cross country gliding flight, what ground structure should be avoided enroute? ^q24

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q24) - A) Stone quarries and large sand areas - B) Highways, railroad tracks and channels. - C) Moist ground, water areas, marsh areas - D) Areas with buildings, concrete and asphalt. Correct: C)

Explanation: Thermal convection depends on differential ground heating. Moist ground, water bodies, and marshes have high thermal inertia and specific heat capacity — they absorb solar radiation without heating up as quickly as dry land, suppressing thermal development above them. Flying over large water areas or wetlands thus means less lift and potentially a forced landing in unsuitable terrain. Conversely, dry fields, rocky areas, and built-up areas with dark surfaces (asphalt, concrete) generate strong thermals.

Q25: During a cross-country flight, you approach a downwind turning point. The point should be taken ... (2,00 P.) ^q25

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q25) - A) As low as possible. - B) As steep as possible. - C) As high as possible. - D) With as less bank as possible Correct: C)

Explanation: At a downwind turning point, the glider must turn and fly back into the wind (or at an angle into it), immediately losing tailwind assistance and gaining a headwind component. Arriving high provides the maximum altitude reserve for the subsequent upwind leg, where groundspeed is reduced and glide distance over ground is shortened. Arriving low with a turn ahead is tactically dangerous — any failure to find lift on the upwind leg leaves no margin for landing field selection.

Q26: After getting around a turning point, what should a glider pilot be prepared for? (2,00 P.) ^q26

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q26) - A) For weakening thermals due to the progressing time - B) For a changed horizontal picture due to lower cloud bases - C) For increased cloud dissipation due to the progressing time - D) For a changed cloud picture due to the apparently changed position of the sun Correct: D)

Explanation: When a glider turns through 90° or 180° at a waypoint, the pilot's perspective of the sky changes dramatically — the sun appears to have "moved" relative to the aircraft heading, and cumulus clouds that were previously in the pilot's peripheral vision or behind may now appear in front, and vice versa. This perceptual shift can make the sky look completely different even if objectively unchanged. Pilots must re-orient their thermal assessment relative to the new heading rather than relying on their previous mental picture.

Q27: According ICAO, what symbol indicates a group of unlighted obstacles? ^q27

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q27)

ICAO Obstacle Symbols

Explanation: ICAO chart symbology for aeronautical charts (defined in ICAO Annex 4 and Document 8697) uses specific symbols to distinguish obstacle types: lit vs. unlit, single vs. group. A group of unlighted (unlit) obstacles is shown with a specific symbol (D in the referenced figure). Knowing these symbols is essential for cross-country flight planning to identify terrain and obstruction hazards that would not be illuminated at dusk or during poor visibility conditions.

Q28: According ICAO, what symbol indicates a civil airport (not international airport) with paved runway? ^q28

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q28)

ICAO Airport Symbols

Explanation: ICAO aeronautical chart symbology differentiates airports by category: civil vs. military, international vs. domestic, and runway surface (paved vs. unpaved). A civil domestic airport with a paved runway is represented by a specific symbol (A in the referenced figure) — typically a circle with a line or specific fill pattern. Glider pilots use these symbols when planning outlanding fields or alternate airports, as paved runways are preferable to grass strips for emergency landings in many conditions.

Q29: According ICAO, what symbol indicates a general spot elevation? ^q29

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q29)

ICAO Spot Elevation Symbols

Explanation: ICAO chart symbols differentiate between spot elevations (general terrain high points), surveyed elevation points, and obstruction heights. A general spot elevation (symbol B in the referenced figure) marks a notable terrain elevation that may not be the highest peak but is charted for situational awareness. Cross-country glider pilots must be familiar with these symbols to identify terrain clearance requirements, especially when planning routes through valleys or near mountain ranges where minimum safe altitudes are critical.

Q30: What distance can be covered during a glide in a glider plane with glide ratio 1/30 from a height of 1500 m? (Neglect wind and thermal effects) ^q30

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^q30) - A) 30 km - B) 45 NM - C) 45 km - D) 81 NM Correct: C)

Explanation: Glide distance = glide ratio × height available. With a glide ratio of 1:30 (30 metres forward for every 1 metre of height lost) and 1,500 m of height: distance = 30 × 1,500 m = 45,000 m = 45 km. Note: 45 NM would be approximately 83 km, which would require a glide ratio of roughly 1:55 — far above this aircraft's performance. The calculation is straightforward in metric: ratio × altitude in metres gives distance in metres. Always verify units — mixing NM and metres is a common error.

BAZL/OFAC — Series 1 Questions

BAZL Br.30 Q1: Why can wing loading be increased when soaring conditions are good? ^bazl301

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_1) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

Correct: B)

Explanation: In active thermal conditions with strong lift, the glider can fly faster between thermals to optimise the average cross-country speed (MacCready theory). A higher wing loading (achieved with water ballast) shifts the speed polar towards higher speeds, improving the glide ratio at high speed. The trade-off is a higher stall speed and a higher best-glide speed — acceptable when thermals are strong enough to compensate.

BAZL Br.30 Q13: The tail wheel of a glider was not removed before departure. What will be the consequence? ^bazl3013

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_13) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

Correct: A)

Explanation: The tail wheel is mounted at the extreme rear of the fuselage, at a large distance aft of the nominal centre of gravity. Even though its mass is small in absolute terms, its large moment arm gives it a significant moment. Leaving the tail wheel installed during flight shifts the C.G. aftward — potentially beyond the aft C.G. limit — making the aircraft pitch-unstable and difficult to control.

BAZL Br.30 Q3: The pilot exceeds the maximum cockpit payload by 10 kg. What must be done? ^bazl303

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_3) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

Correct: D)

Explanation: The maximum pilot seat load is a certification limit that cannot be circumvented by any trim adjustment or ballast reduction. Exceeding the maximum payload may place the C.G. outside the forward limit and subjects the structure to uncertified loads. The only correct action is to reduce the payload (e.g. by removing ballast or equipment) until the limits are respected. Trimming does not alter mass and does not make the aircraft compliant with its limitations.

BAZL Br.30 Q2: What propels a pure glider forward? ^bazl302

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_2) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

Correct: B)

Explanation: A motorless glider is propelled exclusively by the component of the weight vector (gravity) projected in the direction of the flight path. In steady gliding flight, the aircraft is in equilibrium between lift (perpendicular to the flight path), drag (opposing motion) and weight. The component of weight along the flight path axis balances drag and maintains airspeed. Ascending air currents can slow or cancel the descent but do not propel the aircraft forward.

BAZL Br.30 Q12: The current mass of an aircraft is 610 kg and the centre of gravity (C.G.) position is at 80.0. You remove a 10 kg item of baggage located at a moment arm of 150. What is the new centre of gravity? ^bazl3012

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_12) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

Correct: A)

Explanation: Calculation of the new C.G.: Initial moment = 610 × 80.0 = 48,800. Removed moment = 10 × 150 = 1,500. New total moment = 48,800 − 1,500 = 47,300. New mass = 610 − 10 = 600 kg. New C.G. = 47,300 ÷ 600 = 78.833. Since the baggage was located aft of the current C.G. (150 > 80), its removal shifts the C.G. forward, which is consistent with the result obtained (78.833 < 80.0).

BAZL Br.30 Q14: The empty mass of the Discus B is 245 kg. You are planning to carry 184 kg of water ballast. What is the maximum load at the pilot's seat? ^bazl3014

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_14) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

Extract from the Discus B Flight Manual — Loading table with water ballast [figures/bazl_30_q14_discus_loading_table.png] Max. permitted all-up weight including water ballast : 525 kg Lever arm of water ballast : 203 mm aft of datum (BE)

Table of water ballast loads at various empty weights and seat loads:

| Empty mass (kg) | Seat load 70 kg | 80 kg | 90 kg | 100 kg | 110 kg | |---|---|---|---|---|---| | 220 | 184 | 184 | 184 | 184 | 184 | | 225 | 184 | 184 | 184 | 184 | 184 | | 230 | 184 | 184 | 184 | 184 | 184 | | 235 | 184 | 184 | 184 | 184 | 180 | | 240 | 184 | 184 | 184 | 184 | 175 | | 245 | 184 | 184 | 184 | 180 | 170 | | 250 | 184 | 184 | 184 | 175 | 165 |

*Water ballast in both wing tanks (kg). For empty mass 245 kg and ballast 184 kg: the maximum seat load is 90 kg (column 90 kg → value 184, but column 100 kg → 180 and column 110 kg → 170; with ballast=184 required, read the 245 kg row and find the seat load corresponding to ballast=184, i.e. max 90 kg permitted according to the table).*

Correct: C)

Explanation: According to the Discus B loading table (extract from the flight manual): with an empty mass of 245 kg and 184 kg of water ballast in both wing tanks, the maximum seat load is 90 kg. The maximum permitted all-up weight with ballast is 525 kg; according to the row of the table corresponding to 245 kg / 184 kg, the seat load is limited to 90 kg in order to remain within the approved C.G. envelope.

BAZL Br.30 Q7: What important principle must be observed when making an off-field landing on sloping terrain? ^bazl307

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_7) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

Correct: D)

Explanation: On sloping terrain, the fundamental rule is to land uphill, which considerably shortens the landing roll — deceleration is assisted by gravity. An approach speed slightly above normal is recommended to maintain manoeuvrability and safety in the face of possible wind shear or turbulence on low final over unknown terrain. Landing downhill would be extremely dangerous as deceleration would be insufficient.

BAZL Br.30 Q9: You must land in heavy rain. What must you pay particular attention to? ^bazl309

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_9) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

Correct: B)

Explanation: In heavy rain, the wing surface is wet, which can degrade aerodynamic characteristics (surface roughness, modification of the effective aerofoil profile). The stall speed may be slightly higher and the airbrakes less effective due to water on the surface. A higher approach speed therefore provides an appropriate safety margin. A shallower approach angle would be dangerous as it reduces obstacle clearance margins and extends the final approach.

BAZL Br.30 Q10: You are taking off from a grass runway that has become waterlogged after several days of rain. What should you expect? ^bazl3010

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_10) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

Correct: D)

Explanation: A waterlogged grass runway offers greater rolling resistance (friction and soft ground deformation), which increases ground drag during acceleration. In addition, long or rain-flattened grass can create extra resistance. The takeoff distance is therefore longer compared to a dry grass runway. Aquaplaning is possible on hard runways with standing water but does not apply directly to wet grass — and wet grass offers more resistance, not less.

BAZL Br.30 Q8: Which of the following statements is correct at a speed of 170 km/h, taking into account the following speed polar? ^bazl308

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_8) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

ASK 21 Speed Polar: [figures/bazl_30_q08_ask21_speed_polar.png] Two curves: G=470 kp (light mass, min sink rate ~0.657 m/s at ~75 km/h) and G=570 kp (heavy mass, min sink rate ~0.724 m/s). The best glide ratio is read from the tangent from the origin. At 170 km/h, the sink rate is higher for G=570 kp than for G=470 kp.

Correct: C)

Explanation: The ASK21 speed polar is shown for two masses: G=470 kp and G=570 kp. At 170 km/h, reading both curves, the sink rate is higher for the greater mass (570 kp). This is physically logical: a higher mass requires more lift to fly, which results in a higher angle of attack (at the same speed), greater induced drag and therefore a higher sink rate at that speed. The best L/D ratio remains approximately the same as both polars are nearly geometrically similar, but the absolute sink rate increases with mass.

BAZL Br.30 Q11: What is the speed at the minimum sink rate in still air for a mass of 450 kg? ^bazl3011

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_11) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

Speed Polar (AIRSPEED): [figures/bazl_30_q11_speed_polar_450_580.png] Two curves: 450 kg and 580 kg. The minimum sink rate (top of the curve) for 450 kg is at approximately 75 km/h. The 580 kg curve is shifted to the right (higher speeds) and downward (greater sink rate).

Correct: B)

Explanation: The speed at minimum sink rate (V min sink) corresponds to the top of the speed polar curve — the point where the curve is highest (lowest sink rate). Reading the polar for a mass of 450 kg, this point is at approximately 75 km/h. This is the optimum speed for maximising endurance in still air and for centring thermals. It differs from the best glide speed (which corresponds to the tangent from the origin to the polar).

BAZL Br.30 Q15: From what altitude on the route between Murten (approx. N46°56'/E007°07') and Neuchâtel aerodrome (approx. N46°57'/E006°52') are you required to request permission to cross the PAYERNE TMA? ^bazl3015

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_15) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

Correct: C)

Explanation: The PAYERNE TMA has a lower limit that varies by sector. On the route between Murten and Neuchâtel, the lower limit of the relevant TMA is at 700 m AMSL (2300 ft). Below this altitude, flight may be conducted without authorisation in the lower airspace (Class E or G depending on the area). Above 700 m AMSL, authorisation from the responsible ATC unit is required to cross the Class D TMA. This information is found on the Swiss ICAO aeronautical chart 1:500,000 or the gliding chart 1:300,000.

BAZL Br.30 Q16: In which airspace class are you flying at 1400 m AMSL (QNH 1013 hPa) over Birrfeld aerodrome (47°25'36"N/007°14'02"E), and what are the visibility and cloud distance minima in that airspace? ^bazl3016

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_16) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

Correct: A)

Explanation: Birrfeld aerodrome lies within Class E airspace above the local CTR/ATZ. At 1400 m AMSL in this sector, you are in Class E. VFR minima in Class E are: horizontal visibility 5 km, cloud clearance 1500 m horizontally and 300 m vertically. Class E provides an air traffic service for IFR; VFR flights are permitted without a clearance but must comply with these meteorological minima.

BAZL Br.30 Q17: The route shown below towards SCHWYZ (dotted line) is planned for 20 June 2015 (summer time) between 1515–1545 LT at 6500 ft AMSL. Which of the following statements is correct? ^bazl3017

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_17) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

DABS — Daily Airspace Bulletin Switzerland (extract) [figures/bazl_30_q17_dabs_map.png]

| Firing-Nr D-/R-Area NOTAM-Nr | Validity UTC | Lower Limit AMSL or FL | Upper Limit AMSL or FL | Location | Center Point | Covering Radius | Activity / Remarks | |---|---|---|---|---|---|---|---| | B0685/14 | 0000–2359 | 900m / 3000ft | FL 130 | SION TMA SECT 1 | 461610N 0072940E | 4.7 KM / 2.5 NM | TMA SECT 1 ACT HX ONLY | | W0912/15 | 1145–1300 | GND | FL 120 | MORGARTEN | 470507N 0083758E | 10.0 KM / 5.4 NM | R-AREA ACT. ENTRY PROHIBITED. FOR INFO CTC ZURICH INFO 124.7 | | W0957/15 | 1400–1700 | 2150m / 7000ft | FL 120 | HINWIL | 471721N 0084859E | 7.0 KM / 3.8 NM | TEMPO R-AREA ACTIVE. ENTRY PROHIBITED. CTC 118.975 | | W0960/15 | 0800–1700 | GND | 1200m / 4050ft | 1.7 KM SE CERNIER | 470352N 0065442E | 1.5 KM / 0.8 NM | D-AREA ACT |

Correct: B)

Explanation: Consulting the DABS extract provided: zone W0957/15 is active from 1400 to 1700 UTC. On 20 June 2015 (summer time CEST = UTC+2), 1515–1545 LT corresponds to 1315–1345 UTC. Zone W0957/15 is therefore not yet active at this time (it starts at 1400 UTC). Zone W0912/15 is active from 1145 to 1300 UTC — already expired. The route can therefore be flown without coordination between 1500 and 1600 LT (i.e. 1300–1400 UTC), just before W0957/15 becomes active. The DABS applies to all airspace users, including gliders.

BAZL Br.30 Q18: According to the ICAO aeronautical chart at 1:500,000, at what altitude over Schwyz (approx. 47°01' N, 8°39' E) must you request permission to enter Class C airspace? ^bazl3018

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_18) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

Correct: C)

Explanation: Over Schwyz, the Swiss ICAO aeronautical chart 1:500,000 shows the lower limit of Class C airspace at FL 130. Below this, the airspace is Class E (or D depending on the area). Entering Class C requires an ATC clearance regardless of flight rules. Glider pilots flying wave or cross-country flights at high altitude over the Swiss central Alps must therefore contact the competent ATC unit (Zurich Information or Zurich ACC) before reaching FL 130.

BAZL Br.30 Q19: Until what time is La Côte aerodrome (LSGP) open in the evening? ^bazl3019

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_19) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

AD INFO 1 — LA CÔTE / LSGP [figures/bazl_30_q19_lsgp_ad_info.png]

| Data | Value | |--------|--------| | ICAO | LSGP | | Elevation | 1352 ft (412 m) | | ARP | 46°24'23"N / 006°15'28"E | | Runway | 04 / 22 — true/mag: 041°/040° and 221°/220° | | Dimensions | 560 x 30 m — GRASS | | LDG distance available | 490 m | | TKOF distance available | 490 m | | SFC strength | 0.25 MPa | | Status | Private — Airfield, PPR | | Location | 25 km NE Geneva | | Hours MON–FRI | 0700–1200 LT / 1400–ECT –30 min | | Hours SAT/SUN | 0800–1200 LT / 1400–ECT –30 min | | ECT reference | → VFG RAC 1-1 |

ECT = End of Civil Twilight. The aerodrome closes 30 minutes before end of civil twilight.

Correct: C)

Explanation: According to the AD INFO 1 sheet for LSGP La Côte, the afternoon opening hours are shown as "1400–HRH –30 min" where HRH denotes "end of civil twilight" (Swiss notation). The aerodrome therefore closes 30 minutes before the end of civil twilight (not before sunset, which is an earlier moment). This applies on weekdays (MON–FRI) and at weekends (SAT–SUN). PPR (Prior Permission Required) also applies.

BAZL Br.30 Q20: On which frequency do you receive information about winch launches at Gruyères aerodrome (LSGT) at weekends? ^bazl3020

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_20) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

Visual Approach Chart — GRUYÈRES / LSGT [figures/bazl_30_q20_lsgt_approach_chart.png] AD 124.675 — PPR — ELEV 2257 ft (688 m)

Key chart data (altitudes in ft, magnetic headings):

| Data | Value | |--------|--------| | ICAO | LSGT | | AD Frequency | 124.675 MHz | | Elevation | 2257 ft (688 m) | | Status | PPR | | Minimum AD overfly altitude (MNM ALT) | 4000 ft | | Glider ARR/DEP sector W (GLD ARR/DEP W) | MAX 3100 ft | | Glider ARR/DEP sector E (GLD ARR/DEP E) | MAX 3600 ft | | HEL ARR/DEP | 3000 ft | | Preferred ARR sectors | WEST and EAST | | CTN (cross-country traffic) | 3000 ft | | MNM AD overfly | 4000 ft | | Class C airspace above | FL 100 / 119.175 GENEVA DELTA | | Winch launches | Intensive SAT/SUN (CTN: Intense winch launching SAT/SUN) | | Nearby VOR/DME | SPR R076, 113.9 MHz |

Noise-sensitive areas (yellow) around Bulle/Broc. Avoid overflying the field during PJE (parachute dropping). Contact RTF 5 min before ETA.

Correct: C)

Explanation: According to the Visual Approach Chart for LSGT Gruyères, the aerodrome frequency is shown in the top right: AD 124.675. This is the frequency on which local traffic information is broadcast, including information on intensive winch launches at weekends ("Intense winch launching SAT/SUN"). Frequencies 110.85 and 113.9 correspond to the VOR/DME SPR (Saanen/Pringy) shown on the chart, and 119.175 is the GENEVA DELTA frequency.

BAZL Br.30 Q6: What distance do you cover in 90 minutes at a ground speed of 90 km/h? ^bazl306

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_6) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

Correct: D)

Explanation: Distance = speed × time. Ground speed = 90 km/h, duration = 90 minutes = 1.5 hours. Distance = 90 km/h × 1.5 h = 135 km. This is a basic navigation calculation: remember to convert minutes to a fraction of an hour before multiplying. 90 minutes represents one and a half hours, i.e. 1.5 h — not 0.9 h (a common error when confusing minutes with decimal hours).

BAZL Br.30 Q4: At an altitude of 6000 m, the airspeed indicator shows 160 km/h (IAS). The true airspeed (TAS)... ^bazl304

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_4) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

Correct: B)

Explanation: The airspeed indicator measures dynamic pressure, which depends on air density. At 6000 m altitude, the air density is significantly lower than at sea level (standard ISA atmosphere). For the same dynamic pressure (same IAS), the TAS must be higher because less dense air requires a greater true speed to produce the same indicated pressure. In practice, TAS increases by approximately 2% per 300 m of altitude gain. At 6000 m, TAS is approximately 20–25% higher than IAS.

BAZL Br.30 Q5: You are flying in wave lift at 6000 m altitude. What is the maximum speed you may fly? ^bazl305

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_30_5) Source: BAZL/OFAC Serie 1 - Branches Spécifiques

Correct: C)

Explanation: The VNE (never-exceed speed) displayed on the airspeed indicator is an IAS reference value at sea level (or low altitude). At high altitude, the TAS corresponding to the same IAS is higher, but it is the true airspeed (TAS) that determines structural aerodynamic loads. For gliders, the flight manual provides a **speed-altitude table** (or curve) giving the corrected VNE IAS as a function of altitude. At 6000 m, the V_NE IAS to be observed is lower than that shown at ground level — hence the reference to the table displayed in the cockpit.


Series 2 — FOCA/BAZL Mock Exam

BAZL 301 Q1 — 1235 lbs (rounded) correspond to (1 kg = approx. 2.2 lbs): ^bazl3011

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_1) - A) approx. 2470 kg. - B) approx. 560 kg. - C) approx. 620 kg. - D) approx. 2720 kg. Correct: B)

Explanation: 1235 lbs ÷ 2.2 = 561.4 kg ≈ 560 kg (approx.). Formula: mass (kg) = weight (lbs) / 2.2.

BAZL 301 Q2 — What must be particularly observed when landing on an upsloping field with a tailwind? ^bazl3012

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_2) - A) Fly final a little faster than usual. - B) Flare higher than usual. - C) You must land with all airbrakes fully extended. - D) Fly at the normal approach speed (yellow triangle). Correct: D)

Explanation: On an upsloping field with tailwind, fly the normal approach speed (yellow triangle). The upslope shortens the flare distance and tailwind reduces effective landing distance. Normal speed is critical to avoid stall.

BAZL 301 Q3 — In which airspace class are you above Langenthal aerodrome (47 deg 10’58’’N / 007 deg 44’29’’E) at an altitude of 2000 m AMSL (QNH 1013 hPa), and what are the minimum visibility and cloud distance requirements? ^bazl3013

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_3) - A) Class E airspace, horizontal visibility 5 km, cloud clearance: 1.5 km horizontally, 300 m vertically. - B) Class C airspace, horizontal visibility 5 km, cloud clearance: 1.5 km horizontally, 300 m vertically. - C) Class D airspace, horizontal visibility 5 km, cloud clearance: 1.5 km horizontally, 300 m vertically. - D) Class G airspace, horizontal visibility 1.5 km, clear of cloud with continuous sight of the ground. Correct: A)

Explanation: Langenthal at 2000 m AMSL is in Class E airspace (between 1500 ft AMSL and the TMA/CTA floor). In Class E, VMC requires: visibility 5 km, cloud clearance 1500 m horizontally and 300 m vertically.

BAZL 301 Q4 — Which center of gravity position is the most dangerous for a glider? ^bazl3014

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_4) - A) Too far forward. - B) Too high. - C) Too low. - D) Too far aft. Correct: D)

Explanation: A center of gravity too far aft is the most dangerous position as it makes the glider longitudinally unstable. Longitudinal stability disappears and the glider may pitch violently without possible correction.

BAZL 301 Q5 — How does the indicated VNE (never-exceed speed) change as altitude increases? ^bazl3015

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_5) - A) It remains identical. - B) It increases. - C) It remains the same; the airspeed indicator accounts for this automatically. - D) It decreases. Correct: C)

Explanation: VNE remains the same on the airspeed indicator (IAS) because IAS is already corrected for density by design. True airspeed (TAS) increases with altitude, but IAS remains constant.

BAZL 301 Q6 — You have covered a distance of 150 km in 1 hour and 15 minutes. Your calculated ground speed is: ^bazl3016

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_6) - A) 110 km/h. - B) 115 km/h. - C) 125 km/h. - D) 120 km/h. Correct: D)

Explanation: GS = distance / time = 150 km / (1h15 min) = 150 / 1.25 = 120 km/h.

BAZL 301 Q7 — The following NOTAM was published on 18 August (summer time). Which of the following statements is correct? ^bazl3017

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_7) [figures/bazl_301_q7.png] - A) Due to an airshow, a transit clearance for the extended CTR/TMA Payerne and restricted zone LS-R4 must be requested on frequency 135.475 (Payerne TWR) from 02 to 06 September 2013. - B) The extended CTR/TMA Payerne and restricted zone LS-R4 must be strictly avoided every day from 02 to 06 September 2013, between sunrise and sunset. - C) An airshow is taking place in the Payerne area from 02 to 06 September 2013. The TMA Payerne and restricted zone LS-R4 are active each day during this period between 0600 UTC and 1500 UTC as holding areas and airshow demonstration sectors. - D) Due to an airshow from 02 to 06 September 2013, the extended CTR/TMA Payerne is active each day between 0600 UTC and 1500 UTC. The TMA is used as a holding area, the restricted zone LS-R4 as a demonstration and holding area. The area must be strictly avoided. Correct: D)

Explanation: The NOTAM describes activation of extended CTR/TMA Payerne and zone LS-R4 from 2 to 6 September between 0600-1500 UTC as holding and demonstration areas. The region must be strictly avoided during these periods.

BAZL 301 Q9 — What is the best glide speed in calm air for a flying mass of 450 kg? See attached sheet. ^bazl3019

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_9) [figures/bazl_301_q9.png] - A) 55km/h - B) 75km/h - C) 95km/h - D) 135km/h Correct: B)

Explanation: For a flying mass of 450 kg, best glide speed is read from the polar (attached sheet) where the tangent from the origin touches the curve. For 450 kg, this speed is approximately 75 km/h.

BAZL 301 Q10 — A VFR flight will follow the route shown on the map below (dotted line) from APPENZELL towards MUOTATHAL. The route is planned for 19 March 2013 (winter time) between 1205 and 1255 LT. Answer using the DABS below. Which of the following answers is correct? ^bazl30110

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_10) [figures/bazl_301_q10.png] - A) It is not possible to fly the planned route that day. - B) The route can be flown without coordination between 1200 and 1300 LT. - C) The DABS can be ignored as it only applies to military aircraft. - D) You may pass through all relevant danger and restricted zones below 1000 ft AGL or above 10,000 ft AMSL. Correct: B)

Explanation: According to the DABS for 19 March 2013 (winter time) between 1205-1255 LT, the route can be flown without coordination between 1200-1300 LT as the zones are not active during this specific period.

BAZL 301 Q11 — Wing loading is increased by 40% by water ballast. By what percentage does the glider’s minimum speed increase? ^bazl30111

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_11) - A) 0%. - B) 18%. - C) 100%. - D) 40%. Correct: B)

Explanation: With a 40% wing loading increase, minimum speed increases by √1.4 = 1.183, approximately 18%. Stall speed is proportional to the square root of wing loading.

BAZL 301 Q12 — Based on the polar below, which statement applies at a speed of 150 km/h? See attached sheet. ^bazl30112

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_12) [figures/bazl_301_q12.png] - A) the ASK21 has a higher sink rate at higher flying mass - B) the ASK21 has a better glide ratio at lower flying mass - C) the sink rate of the ASK21 is independent of its mass - D) the ASK21 has a worse glide ratio at lower flying mass Correct: C)

Explanation: At 150 km/h, the ASK21's sink rate is independent of its mass because the two polar curves (different masses) intersect at this speed. This is an aerodynamic property of the polar curve.

BAZL 301 Q13 — At Amlikon aerodrome, what is the maximum available landing distance heading East? ^bazl30113

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_13) [figures/bazl_301_q13.png] - A) 780m. - B) 700m. - C) 700 ft. - D) 780 ft Correct: A)

Explanation: At Amlikon, the maximum available landing distance heading East is 780 m according to the AIP Switzerland chart.

BAZL 301 Q14 — From what altitude must you request a transit clearance for the EMMEN TMA between Cham (approx. N47 deg 11’ / E008 deg 28’) and Hitzkirch (approx. N47 deg 14’ / E008 deg 16’)? ^bazl30114

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_14) [figures/bazl_301_q14.png] - A) 3500 ft AMSL. - B) 5000 ft AMSL. - C) 2400 ft AMSL. - D) 2000ft GND. Correct: A)

Explanation: Between Cham and Hitzkirch, the EMMEN TMA begins at 3500 ft AMSL. Below this you are in uncontrolled airspace. Above this you enter the TMA and must obtain clearance.

BAZL 301 Q15 — The maximum permitted payload is exceeded. What action must be taken? ^bazl30115

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_15) - A) Trim aft. - B) Trim forward. - C) Reduce the payload. - D) Increase takeoff speed by 10%. Correct: C)

Explanation: If the maximum allowed payload is exceeded, the only correct action is to reduce the payload. Trimming or increasing takeoff speed does not solve an excessive mass problem.

BAZL 301 Q16 — What is the effect of wind on the glide angle over the ground if the aircraft’s true airspeed remains constant? ^bazl30116

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_16) - A) Wind has no effect on the glide angle. - B) With a tailwind, the glide angle increases. - C) With a headwind, the glide angle decreases. - D) With a headwind, the glide angle increases. Correct: D)

Explanation: With a headwind, the angle of descent relative to the ground increases (the aircraft descends more steeply over the ground). With a tailwind, the angle decreases. Wind does not change the sink rate in m/s, but it changes the ground descent angle.

BAZL 301 Q17 — How does indicated airspeed (IAS) compare to true airspeed (TAS) as altitude increases? ^bazl30117

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_17) - A) It remains identical. - B) It decreases. - C) It cannot be measured. - D) It increases. Correct: B)

Explanation: Indicated airspeed (IAS) decreases relative to TAS as altitude increases, because air density decreases. At high altitude, IAS is less than TAS. At low altitude, they are close.

BAZL 301 Q18 — What must be particularly observed when landing in heavy rain? ^bazl30118

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_18) - A) Wing loading must be increased. - B) Approach speed must be increased. - C) The approach angle must be shallower than usual. - D) Approach speed must be lower than usual. Correct: B)

Explanation: In heavy rain, approach speed should be increased because rain increases drag and can alter aerodynamic characteristics (surface contamination). A higher speed provides a safety margin.

BAZL 301 Q19 — What must a glider pilot take into account at Bex aerodrome? ^bazl30119

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_19) [figures/bazl_301_q19.png] - A) Depending on wind, the traffic pattern for runway 33 may be either clockwise or counter-clockwise. - B) The traffic pattern for runway 33 is clockwise. - C) The traffic pattern for runway 33 is counter-clockwise. - D) The traffic pattern for runway 15 is clockwise. Correct: A)

Explanation: At Bex, the traffic pattern for runway 33 can be either direction depending on the wind, due to terrain constraints. The correct answer is that direction depends on wind conditions.

BAZL 301 Q20 — What is the maximum flying altitude above Biel Kappelen aerodrome (SE of Biel) if you wish to avoid requesting a transit clearance for TMA BERN 1? ^bazl30120

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_20) [figures/bazl_301_q20.png] - A) 3500 ft AMSL. - B) 3500 ft AGL. - C) FL 35. - D) FL 100. Correct: A)

Explanation: Above Biel Kappelen, the BERN 1 TMA begins at 3500 ft AMSL. By staying below 3500 ft AMSL, you do not need a transit clearance.

BAZL 301 Q8 — Which of the following statements is correct? ^bazl3018

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_301_8) - A) New C.G: 78.5, within approved limits. - B) New C.G: 75.5, outside approved limits. - C) New C.G: 76.7, within approved limits. - D) New C.G: 82.0, outside approved limits. Correct: C)

Explanation: CG calculation question: with the attached sheet data, the new CG is calculated at 76.7, within approved limits.


Series 3 — FOCA/BAZL Mock Exam

BAZL 302 Q1 — What is the effect of a waterlogged grass runway on landing? ^bazl3021

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_1) - A) Landing distance will be longer. - B) No effect. - C) The glider risks running off the runway (groundloop). - D) Landing distance will be shorter. Correct: D)

Explanation: A wet grass runway reduces rolling friction and shortens landing distance. Wet grass decreases braking, so the glider stops faster (sliding effect).

BAZL 302 Q2 — At Schänis aerodrome, what is the maximum available landing distance heading NNW? ^bazl3022

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_2) [figures/bazl_302_q2.png] - A) 520 m. - B) 470m. - C) 520 ft. - D) 470 ft. Correct: B)

Explanation: At Schänis, the maximum available landing distance heading NNW is 470 m according to AIP Switzerland.

BAZL 302 Q3 — The current mass of an aircraft is 6400 lbs. Current CG: 80. CG limits: forward CG: 75.2, aft CG: 80.5. What mass can be moved from its current position to arm 150 without exceeding the aft CG limit? ^bazl3023

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_3) - A) 39.45 lbs. - B) 56.63 lbs. - C) 45.71 lbs. - D) 27.82 lbs. Correct: C)

Explanation: CG calculation: current mass 6400 lbs, current CG 80, aft limit 80.5. Moving mass x from current position to arm 150 without exceeding 80.5: (6400×80 + x×(150-80))/(6400+x) = 80.5. Solution: x ≈ 45.71 lbs.

BAZL 302 Q4 — Correct loading of an aircraft depends on: ^bazl3024

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_4) - A) Only compliance with the maximum allowable mass. - B) Correct payload distribution and compliance with the maximum allowable mass. - C) The maximum allowable mass of baggage in the aft section of the aircraft. - D) Only correct payload distribution. Correct: B)

Explanation: Correct loading depends on both respecting the maximum allowable mass AND correct payload distribution (to keep CG within limits). Both conditions are necessary.

BAZL 302 Q5 — What information can be read from this speed polar? (See attached sheet.) ^bazl3025

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_5) [figures/bazl_302_q5.png] - A) only the maximum glide ratio is independent of flying mass, apart from a minor Reynolds number effect. - B) minimum speed is independent of flying mass. - C) in the speed range up to 100 km/h, an increase in flying mass reduces the sink rate. - D) both glide ratio and minimum speed are independent of flying mass. Correct: A)

Explanation: On the speed polar, maximum glide ratio is independent of flying mass (apart from minor Reynolds number effects). Polar curves for different masses have the same maximum L/D but at different speeds.

BAZL 302 Q6 — At what indicated speed do you approach an aerodrome located at an altitude of 1800 m AMSL? ^bazl3026

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_6) - A) At a higher speed than at sea level. - B) At the same speed as at sea level. - C) At a lower speed than at sea level. - D) At the minimum sink rate speed. Correct: B)

Explanation: At 1800 m AMSL, air is less dense. To maintain the same aerodynamic lift, TAS is higher, but IAS (what is read on the ASI) remains the same as at sea level. Therefore approach at the same indicated speed.

BAZL 302 Q7 — At what speed must you fly to achieve the best glide ratio for a flying mass of 450 kg? (See attached sheet.) ^bazl3027

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_7) [figures/bazl_302_q7.png] - A) 70km/h - B) 90km/h - C) 110km/h - D) 130km/h Correct: B)

Explanation: For 450 kg, best glide speed is read from the polar (attached sheet) at the tangent from the origin. For this glider type at 450 kg ≈ 90 km/h.

BAZL 302 Q8 — The maximum aft CG limit is exceeded. What action must be taken? ^bazl3028

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_8) - A) Trim aft. - B) Trim forward. - C) As long as the maximum takeoff mass is not exceeded, no particular action is required. - D) Redistribute the useful load differently. Correct: D)

Explanation: If the aft CG limit is exceeded, redistribute the useful load forward. Trimming is not a structural solution to the CG problem.

BAZL 302 Q9 — Which factors increase the aerotow takeoff run distance? ^bazl3029

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_9) - A) Low temperature, headwind. - B) High temperature, tailwind. - C) Grass runway, strong headwind. - D) High atmospheric pressure. Correct: B)

Explanation: High temperature and tailwind lengthen the aerotow takeoff roll. High temperature reduces air density (less lift), tailwind increases the takeoff distance.

BAZL 302 Q10 — The following NOTAM was published for 18 November. Which of the following statements is correct? ^bazl30210

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_10) [figures/bazl_302_q10.png] - A) On 18 November from 1800 UTC to 2100 UTC, a military night flying exercise will take place in the ZUGERSEE, SUSTEN and TICINO areas. Lower limit: GND, upper limit: max. 15,000 ft AMSL. - B) On 18 November from 1800 LT to 2100 LT, a military night flying exercise will take place in the ZUGERSEE, SUSTEN and TICINO areas. - C) On 18 November from 1800 UTC to 2100 UTC, a military night flying exercise with helicopters will take place. - D) On 18 November, a military night flying exercise will take place in the ZUGERSEE, SUSTEN and TICINO areas. Lower limit: Class E airspace, upper limit: max. FL150. Correct: A)

Explanation: The NOTAM for 18 November shows a military night flying exercise from 1800 to 2100 UTC in the ZUGERSEE, SUSTEN and TICINO regions, between GND and 15,000 ft AMSL.

BAZL 302 Q11 — What is the maximum permitted flying altitude within the CTR of Bern-Belp airport? ^bazl30211

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_11) [figures/bazl_302_q11.png] - A) 3000 ft AMSL. - B) 4500 ft AMSL. - C) 5500 ft GND. - D) 5000 ft AMSL Correct: A)

Explanation: The CTR of Bern-Belp airport has an upper limit of 3000 ft AMSL.

BAZL 302 Q12 — In which airspace class are you above BEX aerodrome at an altitude of 1700 m AMSL, and what are the minimum visibility and cloud distance requirements? ^bazl30212

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_12) [figures/bazl_302_q12.png] - A) Class E airspace, horizontal visibility 5 km, cloud clearance 1.5 km horizontally, 300 m vertically. - B) Class G airspace, horizontal visibility 1.5 km, clear of cloud with continuous sight of the ground. - C) Class C airspace, horizontal visibility 5 km, cloud clearance 1.5 km horizontally, 300 m vertically. - D) Class C airspace, horizontal visibility 8 km, cloud clearance 1.5 km horizontally, 300 m vertically. Correct: A)

Explanation: Above Bex aerodrome at 1700 m AMSL: we are in Class E airspace (between 1500 ft AMSL and the TMA). VMC in Class E: visibility 5 km, cloud clearance 1500 m / 300 m.

BAZL 302 Q13 — What is the sink rate at 160 km/h for this glider at a flying mass of 580 kg? (See attached sheet.) ^bazl30213

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_13) [figures/bazl_302_q13.png] - A) 1,6m/s - B) 1,2m/s - C) 2,0m/s - D) 0,8m/s Correct: C)

Explanation: At 160 km/h for 580 kg, sink rate is read from the polar (attached sheet) ≈ 2.0 m/s.

BAZL 302 Q14 — 550 kg (rounded) correspond to (1 kg = approx. 2.2 lbs): ^bazl30214

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_14) - A) approx. 12,100 lbs. - B) approx. 250 lbs. - C) approx. 2500 lbs. - D) approx. 1210 lbs. Correct: D)

Explanation: 550 kg × 2.2 = 1210 lbs. Formula: lbs = kg × 2.2.

BAZL 302 Q15 — At what speed must a glider fly in calm air to cover the maximum possible distance? ^bazl30215

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_15) - A) At minimum flying speed. - B) At the minimum sink rate speed. - C) At the best glide ratio speed. - D) At the maximum permitted speed. Correct: C)

Explanation: In calm air, to cover the maximum distance, fly at the best glide speed (finesse maximale). This is the optimal speed for gliding.

BAZL 302 Q16 — The mass of a glider is increased. Which parameter will NOT be affected by this increase? ^bazl30216

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_16) - A) Wing loading. - B) Sink rate. - C) Maximum glide ratio (apart from a minor Reynolds number effect). - D) Indicated airspeed (IAS). Correct: C)

Explanation: When glider mass increases, maximum glide ratio remains practically unchanged (mass-independent, apart from Reynolds effects). What changes: minimum speed increases, wing loading increases, sink rate increases.

BAZL 302 Q17 — How long does it take to cover a distance of 150 km at an average ground speed of 100 km/h? ^bazl30217

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_17) - A) 1 hour 30 minutes. - B) 2 hours. - C) 1 hour 50 minutes. - D) 1 hour 40 minutes. Correct: A)

Explanation: Time = distance / speed = 150 km / 100 km/h = 1.5 h = 1 hour 30 minutes.

BAZL 302 Q18 — When preparing an alpine VFR flight along the route shown on the map below (dotted line) between MUNSTER and AMSTEG, you consult the DABS. You intend to fly this route on a summer weekday between 1445-1515 LT. According to the DABS, zones R-8 and R-8A are active during this period. Answer using the DABS map below and the ICAO aeronautical chart 1:500,000 Switzerland. Which of the following answers is correct? ^bazl30218

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_18) [figures/bazl_302_q18.png] - A) It is not possible to fly this route while the restricted zones are active. - B) Restricted zones LS-R8 and LS-R8A may be transited below 28,000 ft AMSL. - C) Restricted zones LS-R8 and LS-R8A may be overflown at 9200 ft AMSL or above. - D) The route can be flown without restriction after contacting 128.375 MHz. Correct: A)

Explanation: According to the DABS, when zones LS-R8 and LS-R8A are active, this alpine route cannot be flown as these restricted zones cover the itinerary.

BAZL 302 Q19 — You wish to obtain clearance to transit the ZURICH TMA. What must you do? ^bazl30219

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_19) - A) First radio contact on frequency 124.7, at least 5 minutes before entering the TMA. - B) First radio contact on frequency 124.7, at least 10 minutes before entering the TMA. - C) First radio contact on frequency 118.975, at least 10 minutes before entering the TMA. - D) First radio contact on frequency 118.1, at least 5 minutes before entering the TMA. Correct: B)

Explanation: For Zürich TMA transit: first radio contact on 124.7 MHz, at least 10 minutes before entering the TMA.

BAZL 302 Q20 — The minimum speed of your glider is 60 kts in straight flight. By what percentage would it increase in a steep turn with a bank angle of 60 deg (load factor n = 2.0)? ^bazl30220

[FR](../SPL%20Exam%20Questions%20FR/30%20-%20Performances%20et%20planification%20du%20vol.md#^bazl_302_20) - A) approx. 20%. - B) approx. 40%. - C) 0%. - D) approx. 5%. Correct: B)

Explanation: Stall speed in turn with load factor n=2.0: Vsturn = Vsnormal × √n = 60 kts × √2 = 60 × 1.414 ≈ 85 kts. Increase = (85-60)/60 × 100% ≈ 41% ≈ 40%.

=== NEW QUESTIONS (from QuizVDS, not yet in set) ===

30 - Flight Performance and Planning

Source: EASA ECQB-SPL (new questions not in existing set) | 10 questions


Q1: The upper limit of LO R 16 equals... See annex (PFP-056) Siehe Anlage 1 ^q1

Correct: B)

Explanation: Restricted airspace areas (LO R) in Austrian and German aeronautical charts specify their upper and lower limits using standard altitude references. The designation '1 500 ft MSL' (Mean Sea Level) means the restriction extends up to that altitude above sea level, not above ground level. 1,500 ft GND (A) would be above ground level and could vary with terrain. 1,500 m MSL (C) confuses feet with metres. FL150 (D) is far higher and is not a typical LO R ceiling.

Q2: The upper limit of LO R 4 equals... See annex (PFP-030) Siehe Anlage 2 ^q2

Correct: C)

Explanation: In Austrian sectional chart notation, restricted area LO R 4 has its upper limit at 4,500 ft MSL (Mean Sea Level). This means all flights must remain below this altitude to avoid the restricted area. 1,500 ft AGL (A) and 1,500 ft MSL (D) are both too low. 4,500 ft AGL (B) references above ground rather than MSL, which would be incorrect for a fixed regulatory limit.

Q3: Up to which altitude is an overflight prohibited according to the NOTAM? See figure (PFP-024) Siehe Anlage 3 ^q3

Correct: A)

Explanation: NOTAM altitude limits are expressed in feet MSL (Mean Sea Level) unless explicitly stated otherwise. The figure PFP-024 shows an upper limit of 9,500 ft MSL, meaning overflight is prohibited up to that altitude above mean sea level. FL95 (B) is a flight level (pressure altitude referenced to 1013.25 hPa) and differs from an MSL altitude. 9,500 m (C) confuses metres with feet, which would be approximately 31,000 ft. Height (D) implies above ground level, which is not specified in this NOTAM.

Q4: (For this question, please use annex PFP-061) According ICAO, what symbol indicates a group of unlighted obstacles? (2,00 P.) Siehe Anlage 4 ^q4

Correct: D)

Explanation: ICAO aeronautical chart symbology distinguishes between single obstacles and groups of obstacles, and between lighted and unlighted ones. The symbol for a group of unlighted obstacles uses a specific ICAO-standard depiction. Based on the PFP-061 annex, symbol 'C' corresponds to the ICAO symbol for a group of unlighted obstacles. The other symbols (A, B, D) represent single obstacles, lighted groups, or other obstacle types per ICAO Annex 4 chart standards.

Q5: (For this question, please use annex PFP-062) According ICAO, what symbol indicates a civil airport (not international airport) with paved runway? (2,00 P.) Siehe Anlage 5 ^q5

Correct: C)

Explanation: ICAO aeronautical chart symbology uses specific symbols for different aerodrome types. A civil airport (not international) with a paved runway is shown by symbol 'A' in the PFP-062 annex. International airports, military aerodromes, and unpaved-runway airports have different symbols per ICAO Annex 4. Selecting symbol 'A' (answer C) correctly identifies the civil airport with paved runway.

Q6: (For this question, please use annex PFP-063) According ICAO, what symbol indicates a general spot elevation? (2,00 P.) Siehe Anlage 6 ^q6

Correct: B)

Explanation: On ICAO aeronautical charts, a general spot elevation (a known terrain height point not associated with an obstacle) is indicated by a specific dot-and-number symbol. Based on the PFP-063 annex, symbol 'B' (answer C) represents a general spot elevation. The other symbols (A, C, D) correspond to maximum elevation figures, obstruction elevation markers, or other elevation-related symbols defined in ICAO Annex 4.

Q7: The term center of gravity is defined as... ^q7

Correct: D)

Explanation: The centre of gravity (CG) is the single point through which the resultant of all gravitational forces on an aircraft acts — it is the point where the total weight is considered to act. It is not synonymous with the neutral point (A), which is an aerodynamic stability reference. It is not the 'heaviest point' (B), as mass is distributed. Options C and D as stated in the question both describe a geometrical midpoint formula, which is not the correct definition of CG.

Q8: The term moment with regard to a mass and balance calculation is referred to as... ^q8

Correct: D)

Explanation: In mass and balance calculations, a moment is the product of a mass and its balance arm (distance from the datum): Moment = Mass × Arm. This fundamental relationship allows CG to be found by summing all moments and dividing by total mass. A sum (A), difference (B), or quotient (C) of mass and arm does not produce a moment in the physical sense.

Q9: The term balance arm in the context of a mass and balance calculation defines the... ^q9

Correct: C)

Explanation: The balance arm (also called the moment arm or lever arm) is the horizontal distance from the datum reference point to the centre of gravity of a particular mass item. It is not the distance from the CG of the aircraft (A), not the datum point itself (B), and not the point through which gravity acts (D — that is the definition of the centre of gravity of the item).

Q10: What is the purpose of interception lines in visual navigation? ^q10

Correct: A)

Explanation: Interception lines (also called line features or catching lines) in visual navigation are prominent linear features on the ground — such as motorways, rivers, coastlines, or railway lines — that a pilot intentionally navigates toward and follows if orientation is lost. By flying toward a known interception line, the pilot can reestablish position. They are not used to continue flight below VFR minima (B), mark en-route airports (C), or show range from departure (D).