RTM.322 Turbofan Variant

[Hood]

I have come across a turbofan variant of the RTM.322, the RTM.322-20 rated at 2,338lbf. The project was circa 1984.
The only aircraft I know of proposed for the engine was the BAe P.164-108A trainer.
I found a diagram of the RTM.322-20 which is attached.
Does anyone have any further details?

Browsing the RB-designations listing I see that Apophenia listed the RB.580 from 1989 (AE 1107/T406 core variant rated at 7,100lbf) which was stated as following on from an RTM.322 turbofan. There is a Flightglobal link but alas....

 

[JFC Fuller]

I can't be very helpful I am afraid but there was a Flight article in their archive that showed a proposed family tree for the RTM.322 including a turboprop variant (RTM.322-11) in addition to the turbofan.

 

[charleybarley]

Just by chance, back in 1984, I ripped out the article and filed it. Issue 14 April 1984. The family tree shows two -20's, 2,200 and 2,800 lb thrust. The fan would have been scaled from the RB211-535E4, an extra axial stage in the compressor and one more in the free turbine. It would compete with the P&WC JT-15D, ie for a new trainer or business jet.

The turboprop -11, 2,400 shp, was aimed at stretches of the Fokker 50 and BAe ATP and ATR42, ie competition for the P&WC 100 series. Apart from a few dimensions that's about it.

 

[Hood]

Thank you charleybarley, it was lucky that you kept that article. It provides useful context to its orgins.
The -20 was indeed pitched by BAe in their P.164 series which until then had used the JT-15D.

 

[Trident]

The fan would have been scaled from the RB211-535E4, an extra axial stage in the compressor and one more in the free turbine.

I know RR have always been big fans (see what I did there?) of scaling, but that seems ambitious. I mean, if nothing else, even the hub/tip ratio was probably going to be radically different.

 

[charleybarley]

Certainly seems ambitious. The Tay used a 44" version of the 71" 535 fan and a 15D-size would have been about 27".

Demonstrator engines are usually? run to prove perceived risky features. Something which was seen as "a daunting task" by Flight, 16 Feb 1985, and which led to a major carve-up after getting it wrong (the engine wouldn't accelerate beyond idle - similar to the first Avon) was the "blend of new technologies" that went into the V.2500. It needed two extra fan boost stages and a fifth row of variable stators in the compressor.

Worse than a major redesign is cancellation of the program because it doesn't work , eg the Silvercrest, again with operability problems.

 

[overscan (PaulMM)]

I checked my copies of Flight Archive PDFs but I don't have that page.

 

[Hood]

I have a further related but slightly tangential question regarding the RTM.322 engine core.

In one of the Kew files on the Tactical Combat Aircraft (TCA) I came across a document regarding worries about the French gaining illicit access to RB.199 technology to improve the SNECMA M88 via Turbomeca's agreement with Rolls-Royce on developing the RTM.322. The document goes on to say that a lot of hard work had been put into IP protection on the RTM.322 contract to try and prevent this leakage.

So my question is, to what extent did the RB.199 influence the design of the RTM.322 engine core, and what technologies might have they been referring to? Compressor or turbine stage?