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Old 7th Apr 2011, 07:59
  #3125 (permalink)  
PJ2
 
Join Date: Mar 2003
Location: BC
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CONF iture;
Originally Posted by PJ2
Things to note, (as per BEA conclusion that the flaps were retracted
Do they mention the slats ?
It would be interesting if you can see anything in the pictures about the slats as it is part of the procedure to deploy them in an attempt to exit a stall situation.
To answer your questions directly, the slats are not mentioned in either preliminary report, and it's not possible to determine the position of the slats from the photographs available on the BEA site. The wreckage and/or the DFDR will tell us soon enough but there is one possibility although it may be looking too deeply.

If the CAS is higher than 100kts, only the slats are available with a selection of Config 1. So for normal operation in flight, the position of the flap drive does not tell us anything about the slats.

If the CAS is below 100kts, selecting Config 1 will bring out the slats and also bring out the flaps to "1", (8.5deg), which is a normal takeoff configuration in, (Config 2 and 3 can also be used for takeoff).

Since the SFCC [for others not familiar, Slat - Flap Control Computer] gets its speed information from the three ADIRUs, [Air Data and Inertial Reference Units] and we know that there was a loss of airspeed data in the three ADRs we don't know how the SFCC would respond to a crew selection of flap 1.

When recovered, I think it will also be interesting to see what the THS [Trim Horizontal Stabilizer] or screwjack position is.

BOAC, we have seen both main gears but not the nosewheel.

PJ2

Last edited by PJ2; 7th Apr 2011 at 08:13.
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