Sponsor Message:
Military Aviation & Space Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
Saab Draken Flygmotor Turbines  
User currently offlineCO 757 200 From , joined Dec 1969, posts, RR:
Posted (11 years 7 months 3 weeks 2 days ago) and read 2874 times:

It is my understanding that the Volvo Flygmotor turbofans that power the Saab Draken of the Sweedish Air Force are actually modified Pratt and Whitney JT8D-22 turbofans, the same very turbines that power the 727. Obviously,it had to go through major modifications to make it suitable for the fighter mission since what it has to do in a Draken is way different than it's mission and performance in a commercial airliner such as the 727.

Anyone have any knowledge on the specific modifications done to the turbine to make it suitable for fighter ops?

6 replies: All unread, jump to last
 
User currently offlineFlight152 From United States of America, joined Nov 2000, 3369 posts, RR: 6
Reply 1, posted (11 years 7 months 3 weeks 1 day 23 hours ago) and read 2800 times:

No, the engines were license built Rolls-Royce Avon 300s. The afterburners are one thing that was added.

User currently offlineCO 757 200 From , joined Dec 1969, posts, RR:
Reply 2, posted (11 years 7 months 3 weeks 1 day 23 hours ago) and read 2812 times:

Whoops!! , I'm bad.....I meant the Saab Viggen, not the Draken! Your on the ball about the Draken though Flight 152!

User currently offlineContact_tower From Norway, joined Sep 2001, 536 posts, RR: 1
Reply 3, posted (11 years 7 months 3 weeks 1 day 8 hours ago) and read 2531 times:

Pratt & Whitney JT8D-22 is correct for the Viggen, only with a reheat chamber attached.

User currently offlineFBU 4EVER! From Norway, joined Jan 2001, 998 posts, RR: 7
Reply 4, posted (11 years 7 months 3 weeks 1 day 7 hours ago) and read 2536 times:

The Viggen engine also differs from the JT-8D in having an additional stage in both the compressor and turbine sections.


"Luck and superstition wins all the time"!
User currently offlineFredT From United Kingdom, joined Feb 2002, 2185 posts, RR: 26
Reply 5, posted (11 years 7 months 3 weeks 1 hour ago) and read 2516 times:

RM8B vs. JT8D
-------------
Additional fan stage giving a total of three, three LP compressor stages rather than six, new HP turbine, reheat, new quadruple fuel nozzles.

Quite an extensive mod.

Cheers,
Fred



I thought I was doing good trying to avoid those airport hotels... and look at me now.
User currently offlineBroke From United States of America, joined Apr 2002, 1322 posts, RR: 3
Reply 6, posted (11 years 7 months 2 weeks 6 days 4 hours ago) and read 2515 times:

The JT8D uses titanium alloy blades throughout the compressor in its civil configuration. This is not so in the -22. At Mach 2, the compressor inlet temperature is about 250 degrees F, a typical temperature rise, at maximum engine power, for each stage of compression is about 50 degrees F. Titanium loses its strength quickly above 800 degrees F.
800-250 = 550 (temperature rise in the compressor to reach 800 F) 550/50 = 11 (maximum number of compressor stages needed to reach 800 F)
The low pressure compressor has about 8 stages (counting the fan)
The high pressure compressor has about 6 more.
The high compressor blades would have to be fabricated from steel. You would do the whole stage to give you a safety margin and to give you equal thermal expansion throughout the compressor.


Top Of Page
Forum Index

Reply To This Topic Saab Draken Flygmotor Turbines
Username:
No username? Sign up now!
Password: 


Forgot Password? Be reminded.
Remember me on this computer (uses cookies)
  • Military aviation related posts only!
  • Not military 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...
Saab Draken @ Miramar... posted Wed Nov 19 2003 22:28:41 by Maiznblu_757
Saab J-350E "Draken" For Sell posted Tue Dec 27 2005 14:55:03 by PETER05
Saab 2000 Awacs posted Thu Jun 22 2006 13:38:01 by Alessandro
Saab Viggen posted Sun Sep 19 2004 02:55:18 by BuyantUkhaa
Saab Gripen Slightly Underpowered? posted Thu Mar 13 2003 20:48:56 by Keesje
Saab 32 Lansen 50th Anniversary posted Sun Nov 3 2002 11:00:54 by Daniel-k
Draken In Nörvenich posted Fri Sep 13 2002 14:18:44 by Rene
Saab Draken Flygmotor Turbines posted Mon Sep 2 2002 17:32:58 by CO 757 200
Saab And There New Spy Plane! posted Tue Jul 23 2002 16:08:49 by Sudden
Is This A RAT On A Saab J35 Draken? posted Fri Oct 12 2007 18:17:29 by MD-90
Saab S-35OE Draken Startup ... Today's Top Photo? posted Sun Jan 28 2007 05:51:16 by CF188A
Saab J-350E "Draken" For Sell posted Tue Dec 27 2005 14:55:03 by PETER05
UAE Buys Two Saab 340 AEW posted Tue Nov 17 2009 07:55:50 by TGIF
Were Saab An Underrated Fighter Designer posted Tue Oct 6 2009 02:34:54 by Spudh
Could Gas Turbines Been Used In A Super Carrier? posted Fri Sep 5 2008 14:10:24 by 747400sp
Saab Promises Gripens Half The Price Of F35 posted Fri Apr 11 2008 18:39:03 by Mortyman
SAAB, Denel In Talks With Embraer (C-390) posted Thu Jan 17 2008 10:36:30 by PPVRA
Spectacular Saab Commercial With Saab Viggen posted Thu Nov 15 2007 10:06:27 by OwlEye

Sponsor Message:
Printer friendly format