PPRuNe Forums - View Single Post - Jet goes down on its way to Medellin, Colombia
Old 8th Dec 2016, 23:10
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lemme
 
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Originally Posted by AerocatS2A
lemme, I only have access to a BAe146-300 speed card and the speeds might be a few knots off compared to an RJ85 for the same weight. That said, it would appear they were far too slow for a glide. Speed for glide is Vfto + 30. Vfto for a 146-300 at 33000 kg is 165 knots, so best glide would have been around about 195 knots. That is with gear down or up, the only thing that would change that speed is flap selection and they wouldn't have been able to do that (unless possibly they already had Flap 18 in the hold).

For the glide, once you get the gear down, if you are unable to select flap, then you increase speed to maintain the 1NM / 1000' gear down glide profile. In other words that 1/1 profile is an easily remembered target that is achievable with the gear down rather than the best the aircraft can do.
My guess is they were descending under power and configuring for landing (flaps, gear) and were not planning a deadstick arrival. It is so easy to see in hindsight, but at that instant, they probably had high hopes they were going to make it and got caught. Thanks for sharing the numbers.
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