# Light Signals — ICAO/SERA.3415 vs VV Answer Key

Switzerland follows ICAO Annex 2 / SERA.3415 exactly — no deviations.
The VV answer key has **9 out of 11** light signal answers wrong.

## In Flight

| Signal | ICAO/SERA meaning | App | VV | VV Q |
|--------|-------------------|-----|-----|------|
| Steady green | Cleared to land | [t10q145](../SPL%20Exam%20Questions%20EN/10%20-%20Air%20Law.md#^t10q145) B) | [VV Q17 p.6](VV/Questionnaire%20toutes%20branches%20VV.pdf#page=6) A) | mismatch |
| Steady red | Give way, continue circling | [t10q146](../SPL%20Exam%20Questions%20EN/10%20-%20Air%20Law.md#^t10q146) A) | [VV Q18 p.6](VV/Questionnaire%20toutes%20branches%20VV.pdf#page=6) B) | mismatch |
| Flashing green | Return for landing | [t10q147](../SPL%20Exam%20Questions%20EN/10%20-%20Air%20Law.md#^t10q147) A) | [VV Q19 p.6](VV/Questionnaire%20toutes%20branches%20VV.pdf#page=6) A) | match |
| Flashing red | Do not land | [t10q148](../SPL%20Exam%20Questions%20EN/10%20-%20Air%20Law.md#^t10q148) C) | [VV Q20 p.6](VV/Questionnaire%20toutes%20branches%20VV.pdf#page=6) A) | mismatch |
| Flashing white | Land and taxi to apron | [t10q149](../SPL%20Exam%20Questions%20EN/10%20-%20Air%20Law.md#^t10q149) B) | [VV Q21 p.6](VV/Questionnaire%20toutes%20branches%20VV.pdf#page=6) C) | mismatch |
| Red pyrotechnic | Do not land for now | [t10q150](../SPL%20Exam%20Questions%20EN/10%20-%20Air%20Law.md#^t10q150) A) | [VV Q22 p.6](VV/Questionnaire%20toutes%20branches%20VV.pdf#page=6) B) | mismatch |

## On Ground

| Signal | ICAO/SERA meaning | App | VV | VV Q |
|--------|-------------------|-----|-----|------|
| Steady green | Cleared for take-off | [t10q151](../SPL%20Exam%20Questions%20EN/10%20-%20Air%20Law.md#^t10q151) C) | [VV Q23 p.7](VV/Questionnaire%20toutes%20branches%20VV.pdf#page=7) A) | mismatch |
| Steady red | Stop | [t10q152](../SPL%20Exam%20Questions%20EN/10%20-%20Air%20Law.md#^t10q152) A) | [VV Q25 p.7](VV/Questionnaire%20toutes%20branches%20VV.pdf#page=7) C) | mismatch |
| Flashing green | Cleared to taxi | [t10q153](../SPL%20Exam%20Questions%20EN/10%20-%20Air%20Law.md#^t10q153) B) | [VV Q26 p.7](VV/Questionnaire%20toutes%20branches%20VV.pdf#page=7) A) | mismatch |
| Flashing red | Clear the landing area | [t10q154](../SPL%20Exam%20Questions%20EN/10%20-%20Air%20Law.md#^t10q154) B) | [VV Q27 p.7](VV/Questionnaire%20toutes%20branches%20VV.pdf#page=7) B) | match |
| Flashing white | Return to starting point | [t10q155](../SPL%20Exam%20Questions%20EN/10%20-%20Air%20Law.md#^t10q155) A) | [VV Q28 p.8](VV/Questionnaire%20toutes%20branches%20VV.pdf#page=8) B) | mismatch |

## Acknowledgement

| Topic | App | VV | VV Q |
|-------|-----|-----|------|
| How to acknowledge (day) | [t10q156](../SPL%20Exam%20Questions%20EN/10%20-%20Air%20Law.md#^t10q156) A) Rock wings | [VV Q29 p.8](VV/Questionnaire%20toutes%20branches%20VV.pdf#page=8) A) | match |
| Wing rocking mandatory? | [t10q157](../SPL%20Exam%20Questions%20EN/10%20-%20Air%20Law.md#^t10q157) B) Not on base/final | [VV Q30 p.8](VV/Questionnaire%20toutes%20branches%20VV.pdf#page=8) A) Oui | mismatch |

## Conclusion

The app answers follow ICAO/SERA.3415 correctly. The VV answer key appears to have systematic errors in the light signals section — answer letters seem shifted. The letter mismatches are NOT due to option shuffling; the VV key genuinely points to wrong options.

Reference: SERA.3415 / ICAO Annex 2 Appendix 1, Table A1-1