Location:Home > Parts information > Turbo of Compressor wheel > Commercial Aviation content from Aviation Week

Commercial Aviation content from Aviation Week

Time:2018-02-18 23:07Turbochargers information Click:

Technolog Commercial Aviation

Discuss this Article 7


on May 19, 2016

Ultrafan is a GTF, GE have challenged the GTF in the patent courts. Have P&W stolen a march on the opposition?


on May 19, 2016

This is to me very fine work by Rolls Royce who are not resting on their laurels but planning and building even better / lower Fuel Burn Jet Engines for the future. Making the Kero work even harder and with less Jet Noise has been the aim of all Engine Builders and lets trust that Rolls can build not just Big Thrust Engines but New Engines for Aircraft such as the A.320 / Boeing ( Max ) 737.


on May 20, 2016

RR have abdicated any position in medium and small commercial turbine markets. Selling of V2500, loss of Gulfstream (and Bombardier on BR700 engine), dissolving of RTM322, the list goes on....
After John Rose retire, RR leadership has made one strategic mistake after another, including the emphasis on Marine when that market has seen similar contraction as the Energy/Oil&Gas business.
Before geared-fan technology was proven technically and commercially robust, the three spool design was more competitive the larger the thrust requirement, hence the focus of RR on large. Problem with RR leadership is they are stuck with this thinking, were in denial and not adapting to the geared-fan change (except with the demonstrator now) and are now stuck with being out of the small and intermediate market for the next 20 years at least.



on May 19, 2016

Guy, I'm not 100% clear here. Is the UltraFan a two-spool design? If so, what's the big difference between what R-R calls its IP spool and what P&W calls the LP spool in the PW1000G, which according to the PW1100G-JM TCDS has a maximum permissible LP rotation rate of 10,047 RPM, nearly 3X that of the LEAP-1A (again according to the TCDS)?

Guy Norris

on May 20, 2016

In the current three-spool Trent family the LPT drives the fan, the intermediate pressure (IP) turbine drives the IP compressor and the high pressure (HP) turbine drives the HP compressor. In the UltraFan, the fan will be driven by the IP turbine, enabling the LPT to be eliminated and effectively creating what Rolls calls a '2.5' shaft engine.


on May 20, 2016

UltraFan is basically two spools - and the 'IP' really becomes the 'LP'. No big difference.

Basically RR starts with the three spool design - to over-simplify the HP turbine and HP compressor are one spool, the IP spool and IP compressor are another spool, and the LP turbine and fan are the third spool.

Step up to UltraFan and you replace the LP turbine & spool driving the fan with a gearset drawing power from what was the IP spool. So now you only have two turbines/spools - HP and what as the IP. Really it is now a two-spool design and the convention HP/LP terminology would apply. RR is just using their legacy terminology to make it clear how the design evolves.

What was the LP spool goes away completely and what was the IP spool remains - and is now the defacto LP spool. The UltraFan has sometimes been referred to as a 2.5 spool design - the 'front' of the third spool (the fan) remains, but the back (turbine) is gone, replaced by gears.

In the same vein the GTF would also be a 2.5 spool design - but going the other way - P&W added gearing to a 2 spool design. Building up and not cutting down.


on May 19, 2016

Wow!---I worked on F-86D with a GE J-47 with afterburner---about 7000 lb thrust---in Morocco in 1957-58----we had one turbine wheel that had to be inspected aobut every 1000 hours----and we ran up our repaired engines in a home made test cell---chaining down the engine in repair dolly with C-124 tie down chains cemented into the concrete apron-----a couple hundred yards away from the 16 B-47s in their revetments. Our engines made a LOT of smoke---these amazing new engines make me drule. Thanks for great info.l.

Copyright infringement? Click Here!