Go Back  PPRuNe Forums > Ground & Other Ops Forums > Questions
Reload this Page >

Exceeding the critical angel of attack

Questions If you are a professional pilot or your work involves professional aviation please use this forum for questions. Enthusiasts, please use the 'Spectators Balcony' forum.

Exceeding the critical angel of attack

Old 4th Feb 2017, 15:24
  #1 (permalink)  
Thread Starter
 
Join Date: Jul 2015
Location: greece
Posts: 10
Likes: 0
Received 0 Likes on 0 Posts
Exceeding the critical angel of attack

Hello

Exceeding the critical angle of attack makes the coefficient of lift drop suddenly and stall will occur , but if we have enough thrust like the fighter jet and we exceeded the critical angle of attack which is approximately 16 degrees can we still have lift ? Is it still called critical angle even if no stall happens ?
waela320 is offline  
Old 4th Feb 2017, 16:13
  #2 (permalink)  
 
Join Date: Feb 2005
Location: flyover country USA
Age: 82
Posts: 4,579
Likes: 0
Received 0 Likes on 0 Posts
If the engine thrust exceeds the aircraft weight, then the only issue is controllability.

But flying beyond the critical alpha? Lowering the nose increases lift - Not exactly my cuppa tea; Sorta negative stability time.
barit1 is offline  
Old 4th Feb 2017, 16:52
  #3 (permalink)  
 
Join Date: Dec 2015
Location: France
Posts: 507
Likes: 0
Received 0 Likes on 0 Posts
There is still lift well beyond the stalling angle of attack.
That's how your high pitch propeller can deliver thrust at very low speeds.
KayPam is offline  
Old 4th Feb 2017, 17:11
  #4 (permalink)  
 
Join Date: Jun 2002
Location: Wor Yerm
Age: 67
Posts: 4
Likes: 0
Received 0 Likes on 0 Posts
Yes it is. The definition of critical angle of attack is... but remember, it's only very special aircraft that can fly stalled (for extended periods) because as Barit stated, the issue then becomes controllability. And as KP said, there is still lift well beyond the critical angle.
Piltdown Man is offline  
Old 4th Feb 2017, 17:17
  #5 (permalink)  
 
Join Date: Feb 2005
Location: flyover country USA
Age: 82
Posts: 4,579
Likes: 0
Received 0 Likes on 0 Posts
Tes, KayPam, but that's not the problem. With the prop, you just drive on, and as long as the average thrust over 30 seconds or so gets you off the ground - all is well.

HOWEVER - Flying the airplane, keeping it under control in the wing's reverse-slope-alpha regine, is a real challenge for engineers and pilots. Kinda like balancing yourself on top of a basketball!
barit1 is offline  
Old 4th Feb 2017, 18:01
  #6 (permalink)  
 
Join Date: Dec 2015
Location: France
Posts: 507
Likes: 0
Received 0 Likes on 0 Posts
Yes you're right it would lead to huge instability. That sounds hilarious, in a simulator.
KayPam is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.