Engines

A forum to discuss all aviation items (not for latest aviation news and military aviation news)

Moderator: Latest news team

Post Reply
User avatar
Advisor
Posts: 3616
Joined: 09 Sep 2004, 03:00
Location: Heart Lies In Rwy 09/27 'D' 'B-3' TaxiTrack
Contact:

Engines

Post by Advisor »

Often a query has intrigued me. How do aircraft companies decide on the engines.

Engines used by the 737 are called the vaccum cleaners of the runway, i hear.

Is there any bench mark or a clear guideline in companies using a particular model/engine type to be used in the air frame.
Aum Sweet Aum.

User avatar
sab319
Posts: 2142
Joined: 29 Nov 2003, 00:00
Location: Mortsel, antwerp, Flanders, Belgium, Europe, Earth, Milky way
Contact:

Post by sab319 »

Well I think the airline just choose the enignes with suits their needs best...

5Y-KQV
Posts: 249
Joined: 21 Apr 2004, 00:00
Location: Nairobi
Contact:

Post by 5Y-KQV »

I would also be interested in knowing whether the performance of a particular airframe (e.g. fuel burn, range, payload etc.) varies significantly with different engines.

Cheers,

Walter.

User avatar
Avro
Posts: 8856
Joined: 28 Apr 2003, 00:00
Location: Belgium

Re: Engines

Post by Avro »

ERach type of engines 'for the same airplane model) has different specifications and performances. That enables the airlines to make a choice which will suit them the best.
Advisor wrote: Engines used by the 737 are called the vaccum cleaners of the runway, i hear.
Well as far as I know they are called vacuum cleaners because the ground clearance of the B737 engine is very low. It has nothing to do with the type of engine, just with the desing of the plane ;)

Chris

5Y-KQV
Posts: 249
Joined: 21 Apr 2004, 00:00
Location: Nairobi
Contact:

Post by 5Y-KQV »

Is it possible to chnage from one type of engine to another e.g. from RR to GE or vice versa on the same aircraft or is the type of engine factored into the manufacture of an airframe making an interchange impossible?

Cheers,

Walter.

User avatar
Avro
Posts: 8856
Joined: 28 Apr 2003, 00:00
Location: Belgium

Post by Avro »

That's exaclty what the B7e7 should be able to do. For the moment you cannot switch from one engine type to the other in just a few hours. It takes a lot of work. But the B7e7 should have that "special" feature.

just my 2 cents

Chris

SN30952
Posts: 7128
Joined: 31 Jul 2003, 00:00

Post by SN30952 »

5Y-KQV wrote:Is it possible to chnage from one type of engine to another e.g. from RR to GE or vice versa on the same aircraft or is the type of engine factored into the manufacture of an airframe making an interchange impossible? Cheers, Walter.
Boeing reused as much technology from the existing 707 and 727 as possible, most notably the fuselage.
The -100 (launched in February 1965, produced in 1969) and -200* series are identifiable by their tubular engine nacelles which are integrated in the wing and project both fore and aft of it. The engines used on the Original 737 models are Pratt and Whitney JT8D turbofans. Only 2 sections were added to the 737-100 fuselage; a 36-in section forward of the wing and a 40-in section aft of the wing to make it a -200. All other dimensions are the same as the 737-100.
The -9, -5, -17, and -17R engines reflect successive improvements in noise reduction, thrust, and maintenance costs.
On the 737-300 the CFM InternationalCFM56 engines came in place of the JT8Ds.
Walter, in the table of that website you can see what types of 737's can accomodate what engines. The CFM56 was larger than the previous P&W unit, so the engine was slung underneath the wing rather than built into it and the bottom surface of the engine nacelle had to be flattened out. 2 sections were added to the 737-200 fuselage; a 44-in section forward of the wing and a 60-in section aft of the wing.
Image
For the -400, 2 sections were added to the -300 fuselage; a 72-in section forward of the wing and a 48-in section aft of the wing.
Seems here interchange is possible.
These quiet engines CFMI meet FAR 36 Stage 3 and ICAO Annex 16 Chapter 3 noise standards. And they require shorter runways...
The Next-Generation 737 -600, -700, -800 and -900 caused a complete redesign of the 30-year old airliner: new wings and revised engines.
Do not try to interchange engines of NG with former types, Walter.

There are basic types of the 737, the Original -100, -200, Classic -300, -400, -500 and Next-Generation (NG) models.

# 737-100 the original
# 737-200 extended 100
# 737-500, 737-600 Shorter -300 and -700
# 737-300, 737-700 stretched 737-200
# 737-400, 737-800 longer -300 and -700
# 737-900 and 900X even longer
and # 737-700IGW, 737-800ERX — military types

And the engines are:
* Pratt & Whitney JT8D (100, 200)
* CFMI CFM56-3 (300, 400, 500)
* CFMI CFM56-7 (600, 700, 800, 900, 900X)

So it looks to me that some CFMI's could be intercangeable?
More than 3,000 Rolls-Royce US-engines have been delivered to Boeing. Not only for the 737's.
Rolls-Royce Deutschland Ltd & Co KG. (BMW) makes aircraft engines for the A380 and other big aircraft.
There is indeed an advantage to these underwing-mounted engines: eye-level acc(ss)essability. Nearly all system maintenance may be performed at eye level. And all servicing of the 737 is accomplished with standard ground equipment.

Also nice to know: all 737 have a smaller cabine width than the originals (3.56) but all are higher and longer. The highest being the-600. The most sold is the -200.
I have landed in a 737-200 on gravel runway in Argentina in the '70. Low-pressure tires were required. What an experience.

5Y-KQV
Posts: 249
Joined: 21 Apr 2004, 00:00
Location: Nairobi
Contact:

Post by 5Y-KQV »

Thanks a million Fons .... I've learnt a lot of new things from your post and referenced website. I really appreciate it.

Warm regards,

Walter :D

SN30952
Posts: 7128
Joined: 31 Jul 2003, 00:00

Answer to the question if engine types can be interchanged

Post by SN30952 »

As Cathay Pacific was the launch customer for the British engine – despite it was only the second airline to order the engine after Thai Airways (TG), its first two B777 airplanes would take part to the extensive Non-Destructive Testing (NDT) campaign. These airplanes, respectively under the N77772 and N77773 registrations, participated to the ETOPS 180 certification of the 777 from day one. The first Cathay aircraft, registered VR-HNA, was rolled off the Boeing production line as the 14th 777 in May 1995, making its maiden flight on the 26 of the same month. Cathay Pacific pilots and engineers operated the first Trent-powered 777 for 910 cycles, out of the total of 1,000 to simulate more than one year in airline use. These flights were made around the normal Asian and Australian routes in February 1996, giving the airline valuable operating experience prior to the Entry Into Service (EIS).
The initial 777 entered service with Cathay Pacific on 17 May 1996 flying from Hong Kong (HKG) to Bangkok (BKK). A further three further 777-200s was delivered between June and October 1996, bringing the fleet total to four aircraft, since the remaining orders were for 777-300s. The addition of 777-200s to the fleet increased flexibility, allowing the airline to match the varying levels of customer demand with an aircraft of appropriate size. The initial services for the 777-200 were the routes from HKG to Tokyo (NRT), Bangkok (BKK), Seoul (SEL), Taipei (TPE) and Osaka (KIX).

A fifth airplane of the type was taken up in the form of the 777-200 registered N7771, the WA001 (first 777 ever built).
Boeing presented the airplane with Part 121 certification as well as new engines: the Pratt & Whitney PW4074s (74,500lb) were removed in favor of Trent 884s (83,600lb).
WA001 was the first of the type to change engine types, as well as customer code (becoming a 777-267, registered B-HNL).

Retrofitting the airplane was in fact more complex than building a new airplane, as the galleys, lavatories or wire bundles for instance are normally installed as whole units through the fuselage before the different sections are joined together. Here is the answer to the question if engine types can be interchanged on an aircraft

User avatar
Advisor
Posts: 3616
Joined: 09 Sep 2004, 03:00
Location: Heart Lies In Rwy 09/27 'D' 'B-3' TaxiTrack
Contact:

Post by Advisor »

I am thankful to SN 30952 for his valuable insight and information on this topic.
Aum Sweet Aum.

Post Reply