You're perfectly right, but still, it's better to have slats deployed whenever needed than not, as fighter aircraft have, but as I found out about the TWA 727 accident where the slat broke loose at high speed, I have my answer for my question.
Cheers!
Originally Posted by
blind pew
BEA nearly lost another Trident 1 in the Clacton hold in the 70s.
We all knew the droop limitations...out by 225 knots and in by 250 knots but most didn't know the Mach limit. The Clacton hold had a max speed of 210, the skipper had gone for a leak and the new boy had selected the droop out entering the hold somewhere around fl250.
The wing went supersonic locally and they descended somewhere around 5000ft before they regained control.
Wow, at just 210kias, the droop changed the camber so much that the airflow became rushed to supersonic? I wouldn't have believed it if I wouldn't learn about it.
Thanks!
Originally Posted by
TURIN
Fighters are designed to fly at high alpha throughout their speed range. Agility is key. Airliners aren't. The autoslat function ON AN AIRLINER is there to stop something silly happening, not to enhance its capability. Have look at the 737 autoslat logic.
I know the exact reason of the above. The "something silly" thing is normally to be avoided without the use of slats, but if it may happen for whatever reason, they should be there to help, but for being limited due to structural stress, as I later and conclusively found it, they are to remain stowed until below a given airspeed.
Originally Posted by
Goldenrivett
Above FL 200 slats / flaps deployment is outside the operating envelope. (Limitations).
See what happened to TWA 841 in 1979.
TWA_Flight_841_(1979)
Bingo! So a catastrophic structural failure might occur when they deploy above a certain EAS.
Thank you!
Originally Posted by
john_tullamarine
Auto slat (extension) is a system facility whereby the LE slats extend without specific pilot command as alpha gets to a critical value ie provides something in the nature of a get-out-of-jail-free card ...
The
B737, for instance, has an autoslat function in some configurations.
There will be other aircraft Types with similar arrangements but I'll leave it to you to do the searches ...
I din't ask what an auto slat is or what it does, I've already covered this. All that I asked was why are the slats not allowed to deploy at higher IAS/MACH. I have already done my search, thank you...!
Originally Posted by
galaxy flyer
..."if I select retract, nothing will happen, right?" Well, the armed the system, selected retract and out came the slats, all snaggled and damaged, a few parts falling to Earth...
I don't know how the emergency extend switches operate (what they do), but it's rather curious, why selecting retract would "out bring" the slats? Don't know how that system works, so it would be interesting to learn.
Originally Posted by
Capn Bloggs
Hardly autoslat? If Bloggs selects the flap so fast the slats aren't out yet, they come out automatically? Me no comprehendo.
Comprehend your own quote, there's the answer! The question was if the autoslat system could extend the slats even with no flaps. Still no comprehendo?