PPRuNe Forums - View Single Post - United 777 "dives" after takeoff from OGG
Old 20th Feb 2023, 07:56
  #65 (permalink)  
ManaAdaSystem
 
Join Date: Aug 2000
Posts: 1,501
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by VHOED191006
I don't know how Simon on the Avherald can come to that conclusion. Planes just don't loose 1,400ft within the span 12 seconds. That comes out to a roughly -7000fpm descent (TAC reports -8,600fpm, so close enough). Something did indeed happen during that departure. FR24 doesn't just randomly start outputting such extreme values.
Setting up a 7000+ rate of descent in 12 seconds is not that easy. You would have to push hard and fast forward. Negative G.
This rate points toward a windshear/microburst event.
A microburst may be difficult to see on a radar. I flew through one many years ago. Only had small red dots on the radar. Heavy rain in the shear, speed increased fast followed by fast drop in speed as we passed under the microburst. Massive rain. All we could manage was a steady descent at ref -10, throttles fully forward and one dot low on the glide.
As we passed out of the shear, airspeed increased really fast again.
ManaAdaSystem is offline