Qantas 747-400 with Pratt and Whitney Engines

[NM]

Many 744 in the world use RR RB211, reason being the triple spool technology that goes with it , at that time when the first 744 came online there were many performance enhancements such as the famous winglets , many Cathay Pacific 744 have RB 211's, the triple spool technology of the 744 was top of the range in it's time.


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The triple spool was not new for the 747-400. It is a feature of all RB211 engines since the early 1970s. Qantas was using RR RB211-524D engines on the 747-200 and -300 aircraft. So the performance benefits of the technology were no doubt part of the engine decision way before the 747-400 orders were placed by QF.

By the time the 744 came along, the GE CF6 had improved their engines beyond the advances in the RB211-524G that RR developed for the 744. And of course it never delivered the performance guaranteed by RR so they eventually added the Trent High Pressure system to make it into RB211-524G-T.

So I believe the decision for QF to use RR engines on the 747-438 was due to the previous investment in RB211-524D on the earlier 747 fleet and not because RR's engine was better than the GE engine offered on the 744. Ultimately I expect the accounting models showed RR was the best option for the 747-438, especially as RR signed up to the performance guarantees relieving QF somewhat of the risk and costs associated with RR not achieving their plan.

Then again, hind sight is a most wonderful thing.

 

[tuppaware]

What a wonderful wealth of knowledge you are NM!

 

[jb747]

Very different engines to fly too. I think you'll find that most of QF's pilots with a 767 background are big fans of the CF6. It was an awesome performer in the 767, and even though the RR had the same thrust (more or less) was a much nicer engine to fly (than the RR). The P&W is best forgotten..it was horrible.

Flare behaviour of the aircraft was dramatically different with the different engines. I remember my first couple of landings in the RR 767s were pretty much arrivals, but neither should have been. We quickly worked out that the CF6 technique of simply slamming the levers closed when you were finished with the engines was a quaranteed way of arriving solidly in the RRs. The technique in the RR is to gently close the levers over a few seconds, and if you get it right, it lands as you hit the lever stops....do that in a GE and you'll float half way down the runway.

The 747ER is a truly lovely aircraft, and it's a pity we didn't buy more of them.

 

[tuppaware]

The 747ER is a truly lovely aircraft, and it's a pity we didn't buy more of them.

Much difference between the ER and Non-ER , flying them that is ?

 

[maninblack]

The 747ER is a truly lovely aircraft, and it's a pity we didn't buy more of them.

Perhaps looking like more of a pity than ever right now.

 

[jb747]

Much difference between the ER and Non-ER , flying them that is ?

Not really. Different weights. A few more fuel pump switches. Basically it just felt like a much more polished aircraft.