Go Back  PPRuNe Forums > Flight Deck Forums > Tech Log
Reload this Page >

Controversial use of Transient engine rating in PT6

Tech Log The very best in practical technical discussion on the web

Controversial use of Transient engine rating in PT6

Old 15th Sep 2023, 15:28
  #1 (permalink)  
Thread Starter
 
Join Date: Sep 2023
Location: Valencia
Posts: 1
Likes: 0
Received 0 Likes on 0 Posts
Controversial use of Transient engine rating in PT6

Good morning! First of all I want to thank you all for all the knowledge shared in this website.

I work in a firefighting company, operating the pt6a-67f. Some pilots (thanks God not so many) tend to use the transient torque engine rating limited to 20 seconds (but not limited in number of excedances) as a normal operation just to get some more performance (climbing stepper so they can get to dump to confined areas, loading a few more gallons when scooping etc).

Even if you are not a genious you can understand this is not an efficient and safe way to operate an engine, at least if you want not to degrade it earlier than normal. I was diving in the official documentation from EASA, FAA and Pratt & Whitney and was not able to find any statement saying "guys, do not go there voluntarily unless you need to save your life, never use it as a normal regime", maybe because it is so obvious...

Could you please provide me with any documentation just to discuss that way to operate?

Thanks a lot!
svickova is offline  
Old 16th Sep 2023, 10:12
  #2 (permalink)  
 
Join Date: Feb 2010
Location: London (FAA CPL/CFI)
Posts: 277
Received 8 Likes on 7 Posts
Might be worth reaching out to these folks

https://www.turbine-training.com/air...-training.html
ahwalk01 is offline  
Old 16th Sep 2023, 10:28
  #3 (permalink)  
 
Join Date: Jun 2001
Location: OZ
Posts: 1,134
Received 12 Likes on 6 Posts
Hey svickova I think you need to contact P&W to see what they think.
mustafagander is offline  
Old 16th Sep 2023, 19:55
  #4 (permalink)  
 
Join Date: Mar 2018
Location: Central UK
Posts: 1,711
Received 224 Likes on 101 Posts
I'm sure P & W's lawyers will agree with the OP in that "transient" excursions are regarded as unplanned momentary operational exceedences and should never be used wilfully or deliberately, let alone routinely. I'd be astonished if that were not so.A "transient" exceedence occurs in an unexpected event when the "Oh Christ oh **** oh dear" situation results in an input that produces a "woops!" response which is almost immediately cancelled/reduced. Seems pretty self-evident to me. And furthermore I'd hate to try arguing a defence of that practice against an FAA lawyer.
meleagertoo is offline  
Old 20th Sep 2023, 03:14
  #5 (permalink)  
 
Join Date: Aug 2006
Location: Hedge
Posts: 230
Received 24 Likes on 7 Posts
This is my opinion only and I know others will differ.

Transient limits are never to be used during routine operations.

If using transient limits on a frequent basis then you have a problem with Op Specs or personnel skill/training.







Salusa is offline  
Old 21st Sep 2023, 02:15
  #6 (permalink)  
 
Join Date: Mar 2005
Location: N/A
Posts: 6,067
Received 559 Likes on 261 Posts
Some background.

https://www.ecfr.gov/current/title-1.../section-33.87
megan is online now  
Old 29th Sep 2023, 22:46
  #7 (permalink)  
 
Join Date: Apr 2005
Location: yyz
Posts: 111
Received 9 Likes on 8 Posts
Originally Posted by meleagertoo
I'm sure P & W's lawyers will agree with the OP in that "transient" excursions are regarded as unplanned momentary operational exceedences and should never be used wilfully or deliberately, let alone routinely. I'd be astonished if that were not so.A "transient" exceedence occurs in an unexpected event when the "Oh Christ oh **** oh dear" situation results in an input that produces a "woops!" response which is almost immediately cancelled/reduced. Seems pretty self-evident to me. And furthermore I'd hate to try arguing a defence of that practice against an FAA lawyer.
Many years ago we had a free with a torque guage failure fly the 1900 at something like 150% for a day prob 3 legs. The next crew immediately noticed and returned to gate, dumped the pax, and sent for MX..... It turns out they had been driving about 5 hours that way. They were company "problem children". They couldn't understand the higher speeds, fuelflow, temps or use of rudder. They pulled the engine e and sent to overhaul, it came back with fresh overhaul but no new parts.....They built the PT6 tough!
rigpiggy 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.