Go Back  PPRuNe Forums > Aircrew Forums > Rotorheads
Reload this Page >

Jammed Controls - Instances?

Rotorheads A haven for helicopter professionals to discuss the things that affect them

Jammed Controls - Instances?

Old 21st Jun 2020, 15:10
  #61 (permalink)  
 
Join Date: Dec 2014
Location: Africa
Posts: 370
Originally Posted by JimEli View Post
I don't want to hijack this thread, however, this can not go unchallenged. As an AS350 instructor since 1995, having performed literally countless AS350 aircraft and simulator stuck pedals, I find your statement inconceivable. But certainly, don't take my word for it:

Simulated Failure Procedure FFS AS350 B3/H125 - Tail Rotor Control Failure

Stuck Pedal Landing Procedures

Stuck Pedal

Stuck Pedal Run on in AS-350

N1883H Aerospatiale AS350 Stuck Pedal Practice

AS350 Stuck Pedal Landing

etc...

Note: the official Airbus Helicopter’s video (first one) demonstrates a condition where the linkage between the pedals and T/R has been severed. The pedals are free to move, however, the T/R is in a “fixed pitch” position.

LAX07IA115
One can agree with Gordy that the manual is useless: OK, everything the manual says is correct but one has to know prior what is correct, and then read the text several times to understand what they indeed mean. Anyway, who has time during an emergency to study the manual...

On the other hand, JimEli, all the five videos that you pulled out demonstrate the stuck right pedal procedure (what the manual calls "control failure", the TR being stuck a high angle of attack). What Gordy described was a stuck left pedal scenario (what the manual calls "TR Drive failure")! In the context if this educational thread started my Mick Cullen, Gordy admits that at the time he misdiagnosed the type of TR failure he was having and applied the "stuck right pedal" procedure. We are grateful to Gordy for his vivid account of his stuck TR experience! I just brings home how important it is to figure out if you have too much, or too little anti-torque before deciding on your course of action.
Hot and Hi is offline  
Old 21st Jun 2020, 19:03
  #62 (permalink)  
 
Join Date: Dec 2006
Location: yes
Posts: 230
Originally Posted by Hot and Hi View Post
One can agree with Gordy that the manual is useless: OK, everything the manual says is correct but one has to know prior what is correct, and then read the text several times to understand what they indeed mean. Anyway, who has time during an emergency to study the manual...

On the other hand, JimEli, all the five videos that you pulled out demonstrate the stuck right pedal procedure (what the manual calls "control failure", the TR being stuck a high angle of attack). What Gordy described was a stuck left pedal scenario (what the manual calls "TR Drive failure")! In the context if this educational thread started my Mick Cullen, Gordy admits that at the time he misdiagnosed the type of TR failure he was having and applied the "stuck right pedal" procedure. We are grateful to Gordy for his vivid account of his stuck TR experience! I just brings home how important it is to figure out if you have too much, or too little anti-torque before deciding on your course of action.
Thank you for your comment, however I believe you are incorrect in a couple of respects.

First you ask, “who has time during an emergency to study the manual…”

Gordy himself said as much,

“I elected to fly back to the nearest airport with crash rescue facilities----not pessimistic, just stacking the odds in my favor, plus it gave me 30 minutes of transit time to figure it out in my head.”

And later,

“I had enough fuel for about an hour, so I was in no rush.

Second, the manual has a procedure for “Tail Rotor Control Failure”. The procedure is sometimes referred to as a “stuck pedal”, and applicable to situations regardless of the pitch of the tail rotor (full left to full right). It is applicable to situations under which the pedals are “jammed” or “stuck” and also when linkage between the pedals and the tail rotor has been severed. I suggest closely watching the second video which points out the distinction.

Tail Rotor Drive Failure covers a completely different situation. If you pilot an AS-350 helicopter and don’t understand the distinction between the above malfunctions and their emergency procedures, I suggest seeking additional instruction on the matter.

Also note, there is another RFM procedure entitled, “Flight Control Hardover or Servojam”. This can manifest itself in the pedals as either, uncommanded movement or higher than normal force to move the pedals. However, it is related to a specific type of hydraulic malfunction.

Last edited by JimEli; 22nd Jun 2020 at 16:33. Reason: added clarification
JimEli 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 - Do Not Sell My Personal Information

Copyright © 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.