a restatement for those coming to the thread late
New arrivers to the thread may keep finding references to the "in air mode" hypothesis.
To prevent the same questions again and again it might be useful to explain that it goes roughly like this (using lay terms throughout)
1. When (and only when) in the air, the RAT probe is heated (anti-ice). Certain.
2. The first take-off was aborted due to RAT probe being heated when on the ground. Definite.
3. Mechanic "rectified" inappropriate RAT probe heating by disconnecting the heater. Fairly definite.
4. Hypothesis: Mechanic did nothing else, not finding why this heating was happening.
5. Hypothesis: The reason for the heating was a fault with the system which senses (from weight on landing gear) that the aircraft is on the ground. This would mean that the aircraft "thought" that it was in the air throughout, so turned the heater on.
6. This aircraft will warn if flaps/slats are not deployed for take-off, but not if it thinks it is in the air. Fairly definite.
7. Hypothesis: Flaps/slats were retracted for the taxi back after the abort, and reconfiguring them for take-off was forgotten.
8. Conclusion: The take-off could have been without flaps/slats, and due to the hypothesized fault, the normal warning signal would have been absent.
Last edited by fg32; 28th Aug 2008 at 14:22.