Flying-Tiger From Germany, joined Aug 1999, 4195 posts, RR: 33 Posted (10 years 7 months 2 weeks 3 days 18 hours ago) and read 4394 times:
Has there ever been a serious attempt to re-engine the B737-200, e.g. with the BR710/715? There are still quite a few 737-200s out there, a plane which is despite its age still quite popular - and right-sized for many markets. Instead of spending about 25-30 million USD on an Embraer 195, you would probably only need to spend 5-10 million USD on new engines but extend the life of the bird by quite a bit.
DfwRevolution From United States of America, joined Jan 2010, 1138 posts, RR: 51
Reply 1, posted (10 years 7 months 2 weeks 3 days 18 hours ago) and read 4373 times:
I seriously doubt the economics of such a conversion would be favorable. It's why no DC-9 reengine programs have taken place: it's too expensive and the airframes don't have enough cycles remaining to amortize the investment.
AA may consider reengining their MD80 fleet, but it is much younger and much larger than the handful of 732 fleets remaining...
Bluewave 707 From United States of America, joined Jun 2001, 3160 posts, RR: 6
Reply 4, posted (10 years 7 months 2 weeks 3 days 13 hours ago) and read 4175 times:
Would be interesting to see BR715s on a 733 or 735 since those airframes are not as old as 732s. It would make it available for ultra-short range & high-frequency routes like Hawaii's inter-island routes that AQ has. The BR715 has proven itself on HA's 712s.
"The best use of your life will be to so live your life, that the use of your life will outlive your life" -- D Severn
Pilotpip From United States of America, joined Sep 2003, 3164 posts, RR: 10
Reply 10, posted (10 years 7 months 2 weeks 2 days 23 hours ago) and read 3920 times:
There is a hushkit mod available for the 732. Take a look in the database at N767TW and N737TW. Ameristar Air Cargo has these weird birds and we see them at STL from time to time.
Also, if you've ever looked at a 737 of any variety you'll notice there is very little clearance between ground and the bottom of the nacelle. The landing gear on the models with a CFM engine are actually a little longer to get the wing higher (I have to use an extra step on the ladder when fueling these). A wider diameter engine like a BR715 might not be a realistic option as they may have to do other structural changes as Hawk21M mentioned.
AeroWeanie From United States of America, joined Dec 2004, 1612 posts, RR: 51
Reply 11, posted (10 years 7 months 2 weeks 2 days 20 hours ago) and read 3900 times:
Quoting Pilotpip (Reply 10): There is a hushkit mod available for the 732. Take a look in the database at N767TW and N737TW. Ameristar Air Cargo has these weird birds and we see them at STL from time to time.
That hushkit you are looking at is the original Nordam hushkit. It met Stage III, but it increased aircraft drag by ~7%. Nordam went back and redesigned the hush kit using internal mixers and absorbers to meet Stage III, without the drag penalty. AvAero later copied their design. All three of these hush kits also have an inlet guide vane respacing that adds a little length to the forward nacelle.
HAWK21M From India, joined Jan 2001, 31851 posts, RR: 54
Reply 12, posted (10 years 7 months 2 weeks 2 days 17 hours ago) and read 3870 times:
Quoting Pilotpip (Reply 10): The landing gear on the models with a CFM engine are actually a little longer to get the wing higher (I have to use an extra step on the ladder when fueling these).
Not on the B733/4/5. The Landing gear is the same as for the B731/2s.Hence the CFM56-3s have a flat under surface to improve ground Clearence.
The B736/G/8/9 have a higher MLG.Hence the CFM56-7s have a more rounded Inlet.And the NGs stand higher.
On the 732 the upgrade would be very expensive for several reasons as other have noted.
1. The controls in the cockpit are very custom to the JT-8D's. Quite a bit of rewiring would need to occur to re-engine.
2. One would need to rebuild the wing structure for the 733 pylon. This brings up a weight/balance issue. The 733 engine is moved "forward and up" in order to improve the ground clearance (and aerodynamics). Even then the "flattened nacelle" that others have mentioned is required. Personally, I suspect that the balance issues where key in preventing a 732 and DC-9 re-engine. On airframes such as the 742/743 where the engines are right about at the center of gravity and replacements can fit into the same "envelope," this isn't an issue.
Also note that A and B have dramatically improved their manufacturing efficiencies in the last 5 years. This has shifted the decision point a bit toward new aircraft vs. used due to the lower prices being offered.
Quoting ZSOFN (Reply 5): Not really a re-engineering, looks good though!
Yes it does and it makes much more economic sense to do winglets than new engines. The cost is less and thus the "breakeven point" is many years closer in.
Quoting NZ1 (Reply 13): I've always thought a GE90 powered 732 would make a great plane to fly on. Just think of the climb rate, or descent rate when the thrust tears the wings off....
You watched the pod racing in Star Wars episode 1 too many times... Alas, as an engine nut, I approve of a nacelle the same diameter as the passenger compartment. Ok, back to our regularly scheduled tech ops...
Quoting DfwRevolution (Reply 1): t's too expensive and the airframes don't have enough cycles remaining to amortize the investment.
As usual an excellent and concise description.
HA! My drone is lighter than required for registration.
ZSOFN From United Kingdom, joined Jun 2005, 1450 posts, RR: 5
Reply 18, posted (10 years 7 months 2 weeks 8 hours ago) and read 3608 times:
Thinking about it, surely a re-engineering of the 732 already exists. It's called a 735
By the time all the R&D is done & manufacturing capabilities have been established, the costs of the project far outweigh any benefit over just getting hold of second hand -500s or even newer -600s.
Obviously there have been other models to look back on, for instance the KC-135R having CFMs. This may well be a way of keeping these aircraft flying, but in the case of the 737 the 1st generation have had their time. Constantly upgrading older aircraft is a costly procedure. Think about it as though you were running a car. After a certain age, it becomes cheaper to scrap and put money into a newer replacement.
Jetstar From United States of America, joined May 2003, 1737 posts, RR: 10
Reply 19, posted (10 years 7 months 2 weeks 2 hours ago) and read 3568 times:
To re-engine an airplane is a very expensive proposition, especially if the airframe manufacturer does not cooperate.
In the past 20 or so years there have only been a few successful re-engine programs. The USAF KC-135’s, and the DC-60’s upgraded to the CFM-56’s and the Lockheed JetStar, Falcon 20 and the Hawker corporate jets to the TFE 731 engines, in all of these cases, the manufacturer cooperated. Lockheed used the design of the upgrade to the 731 engines when they reopened production of the JetStar and called their version the JetStar 2.
With the airframe manufacturer support, the original structural data can be used as a baseline when the engine upgrade is designed. Without this, the upgrade company has to reverse engineer the section of the airframe to get the structural data needed for certification.
One major candidate for a re-engine program is the Gulfstream 2 and 3 business jets, to replace the noisy and gas guzzling Spey engines with newer modern engines. Gulfstream, the manufacturer will not support any program because they feel it would cut into sales of their newer airplanes and also from a product labiality standpoint, by not supporting the upgrade, they have no involvement in any lawsuit that would arise from a incident involving the airplane and its upgraded engines
Andz From South Africa, joined Feb 2004, 8582 posts, RR: 9
Reply 21, posted (10 years 7 months 1 week 6 days 3 hours ago) and read 3467 times:
Quoting Airplanepics (Reply 8): I believe this is the hush kit system that has been fitted to the engines.
Quoting AeroWeanie (Reply 9): That means the engines have the Nordam or AvAero hush kit installed to allow them to be compliant with ICAO Chapter 36 Stage III noise rules.
I thought about this but most hush-kits I have see involve an extension at the rear of the engine, while on this aircraft the engines looked identical to those on all other 732s operating here. I realise that the reverser buckets prevent anything being fitted behind the engine so how does one hush-kit a 732?
After Monday and Tuesday even the calendar says WTF...
AeroWeanie From United States of America, joined Dec 2004, 1612 posts, RR: 51
Reply 22, posted (10 years 7 months 1 week 6 days 1 hour ago) and read 3445 times:
Quoting HAWK21M (Reply 16): The Only B732 Improvements Available are the "TE Aft flap tilt" & the "Winglets" to Improve Lift.
There are no winglets STCed for use on a 737-200. The only performance enhancing STCs are the AvAero and QuietWing flap droops.
Quoting HAWK21M (Reply 20): It seems they were removed after the lease period.
It turns out that they were non-flightworthy parts installed for an airshow.
Quoting HAWK21M (Reply 20): On Ground Stage III compliant Hushkits dont really sound quieter
Stage III has three noise measurement points: approach, fly-over and departure. Ground noise is not considered.
Quoting Andz (Reply 21): I thought about this but most hush-kits I have see involve an extension at the rear of the engine, while on this aircraft the engines looked identical to those on all other 732s operating here. I realise that the reverser buckets prevent anything being fitted behind the engine so how does one hush-kit a 732?
The later Nordam and AvAero 737-200 hush kits involve internal mixers and acoustical treatment. Except for the stretch of the forward nacelle due to the inlet guide vane respacing, the nacelles for these hush kits are identical to a baseline 737-200. Only the original Nordam hush kit brought in external air for mixing.