Sponsor Message:
Aviation Technical / Operations Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
Dassault Falcon Thrust Reverser  
User currently offlineCorsair2 From United States of America, joined Jan 2001, 248 posts, RR: 0
Posted (8 years 2 months 1 week 1 day 20 hours ago) and read 4489 times:

Recently I was returning from a flight and saw a Dassault Falcon 900 landing. I noticed that it only has one thrust reverser and it is on the center tail engine. It was an awesomely loud noise! Why did Dassault only use one thrust reveser in the design of this plane? If the T/R fails can one defer it through the MEL (Minimum Equipment List)?


"We have clearance Clarence. Roger, Roger. What's our vector Victor?"
8 replies: All unread, jump to last
 
User currently offlineN231YE From , joined Dec 1969, posts, RR:
Reply 1, posted (8 years 2 months 1 week 1 day 20 hours ago) and read 4484 times:

Like on the Airbus A380, which only has 2 "thrust reversable engines," and the BAe 146/ Avro RJ85, which doesn't have any, thrust reversers are used as a helpful supplement and to reduce wear on the brakes, but are often not needed.

Why The Airbus A380 Has Only Two Thrust Reverser? (by 747400sp Jul 2 2006 in Tech Ops)

Thrust Reverser Importance (by Videns Dec 11 2004 in Tech Ops)


User currently offlineCorey07850 From United States of America, joined Feb 2004, 2528 posts, RR: 5
Reply 2, posted (8 years 2 months 1 week 1 day 19 hours ago) and read 4471 times:

Don't know how accurate this is, but I was once talk that noise of Falcons during reverse is actually compressor stall... Again, don't know how valid that is though

User currently offlineCorsair2 From United States of America, joined Jan 2001, 248 posts, RR: 0
Reply 3, posted (8 years 2 months 1 week 1 day 17 hours ago) and read 4443 times:

N231YE- That makes sense. Having more thrust reversers would also be more parts to fix when it is broken. When an airplane is on an MEL restriction (i.e. MD-80 with JT8D-219's) for one thrust reverser inop it can only be deferred for a short time period.

Corey07850- It probably is a compressor stall as the back pressure on the compressor from the T/R disrupts the airflow and cause the compression ratio to be out of synch with N1/N2 rpm.



"We have clearance Clarence. Roger, Roger. What's our vector Victor?"
User currently offlineBAe146QT From United Kingdom, joined Sep 2006, 996 posts, RR: 0
Reply 4, posted (8 years 2 months 1 week 1 day 11 hours ago) and read 4392 times:

Quoting Corsair2 (Reply 3):
It probably is a compressor stall

Really? I thought that such events were generally considered a Bad Thing.

Normally that's because a stall means that either your engine is worn out or you took off with a high crosswind component.

But surely the stall itself causes damage? It's basically hot and dirty combustion gasses being blown forward into your nice shiny fan - which isn't designed for it - because of a low pressure region around the fan disk, isn't it?

To put it another way, is there realy ever a time when a compressor stall is considered a positive thing? Or even acceptable?



Todos mis dominós son totalmente pegajosos
User currently offlineFly2HMO From , joined Dec 1969, posts, RR:
Reply 5, posted (8 years 2 months 1 week 1 day 8 hours ago) and read 4372 times:

I highly doubt it is from a compressor stall. The engine would spool down and die, not up. It's probably just the shear from the exhaust being sharply redirected.

JT8Ds make one hell of a racket when in reverse, and they're not stalling.

Quoting Corsair2 (Reply 3):
It probably is a compressor stall as the back pressure on the compressor from the T/R disrupts the airflow and cause the compression ratio to be out of synch with N1/N2 rpm.

I was taught in turbines class that unless you actually block the exhaust someway, the pressure ratio remains the same, therefore, T/R has no effect.


User currently offlineLiedetectors From United States of America, joined Jul 2005, 360 posts, RR: 0
Reply 6, posted (8 years 2 months 1 week 1 day 7 hours ago) and read 4353 times:

When you design airplanes, you design it such that items such as T/Rs are considered nonessential items, that way if it should fail prior to the flight, you can still dispach. Also while it is nice to have them, landing and stoping distances are computed assuming no T/R. All the certified landing and stoping distances are determined without the T/R as well. As mentioned before, airplanes such as the A380 only have two, the BAe 146 doesnt have any, and they are locked out all together on the F100, clearly, the TR is nonessential to normal operations.

Should the T/R fail when deployed on landing, the pilots are trained to take action to stop with out them.



If it was said by us, then it must be true.
User currently offlineG4doc2004 From United States of America, joined Feb 2004, 123 posts, RR: 0
Reply 7, posted (8 years 2 months 1 week 19 hours ago) and read 4320 times:

I work on a 900, S/N 39. The center reverser is indeed on the MEL, but landing weights and runway lengths are more critical, as is why the flightcrew is briefed if the TR is MEL'd. The brakes on the 900 are pretty stout. As for the noise, it is merely the core air hitting the buckets.....most TR buckets are vertically oriented, so alot of the noise is directed up. These TR's are oriented horizontally, so more of the noise of the high speed core air being suddenly redirected is heard.


"Failure to prepare is preparing to fail"--Benjamin Franklin
User currently offlineN231YE From , joined Dec 1969, posts, RR:
Reply 8, posted (8 years 2 months 1 week 19 hours ago) and read 4317 times:

Quoting Corsair2 (Reply 3):
When an airplane is on an MEL restriction (i.e. MD-80 with JT8D-219's) for one thrust reverser inop it can only be deferred for a short time period.

I apologize about any word confusion; if the T/R is broken, then obviously, it is to be fixed, otherwise, it isn't a necessity for most landings (when it is working).


Top Of Page
Forum Index

Reply To This Topic Dassault Falcon Thrust Reverser
Username:
No username? Sign up now!
Password: 


Forgot Password? Be reminded.
Remember me on this computer (uses cookies)
  • Tech/Ops related posts only!
  • Not Tech/Ops related? Use the other forums
  • No adverts of any kind. This includes web pages.
  • No hostile language or criticizing of others.
  • Do not post copyright protected material.
  • Use relevant and describing topics.
  • Check if your post already been discussed.
  • Check your spelling!
  • DETAILED RULES
Add Images Add SmiliesPosting Help

Please check your spelling (press "Check Spelling" above)


Similar topics:More similar topics...
Question About Thrust Reverser Types posted Tue Aug 15 2006 03:56:23 by YULspotter
744 Thrust Reverser Positioning Sensors posted Sun Jul 9 2006 22:15:03 by Andz
Why The Airbus A380 Has Only Two Thrust Reverser? posted Sun Jul 2 2006 14:26:20 by 747400sp
Stuck Thrust Reverser(?) On CRJ2 posted Mon Apr 17 2006 17:42:07 by FlightShadow
The Best Thrust Reverser? posted Thu Dec 22 2005 21:38:06 by Lockheed
A340-500 Thrust Reverser Deployment posted Sun Apr 3 2005 05:56:02 by Videns
Thrust Reverser Importance posted Sat Dec 11 2004 06:51:32 by Videns
Auto-Thrust-Reverser? posted Thu Oct 14 2004 13:23:05 by FRASYD
Thrust Reverser Effectiveness? posted Thu Jul 22 2004 06:27:17 by Concord977
767 Thrust Reverser Question posted Tue Mar 23 2004 09:34:47 by Hardkor

Sponsor Message:
Printer friendly format