Red Admiral
22nd November 2008, 11:43
Last week I spent an afternoon going around Rolls-Royce works at Bristol, unfortunately I have no pictures as its pretty much all defence related work that goes on and they're hot on security.
Firstly we had a talk from one of the engineers leading the Lift-Fan system for the Joint Strike Fighter. He gave us a brief overview and then went down in levels of details to give us more of picture of what his team was working on. They're having rather severe problems and overall it did more to convince me that a PCB engine with thrust vectoring is a much simpler and safer idea. For the JSF option, there is an aft mounted engine and a drive shaft forwards to a clutch, gearbox and a contra-rotating liftfan. The engine thrust mounts are at the back and the lift fan is fixed at the front. As the engine heats up during operation there is considerable stress imposed on the drive shaft and clutch. Both are critical systems for VTOL flight and so very few failures can be tolerated. Thats where the problems come in.
After this we had a short tour around the factory floor where they are making engines. It was quite interesting for me personally as they're vertically mounted and made up in modules. For non-defence there was EFE (Environmentally Friendly Engine) being made up which is due to go on tests next year to test new technologies. The main aim is for reduced emissions and greater efficiency through higher turbine temperatures, it was initially aimed at a more active cooling system for the turbine blades but this seems not to be possible. (HP air bled off the compressor, cooled and then going through the turbine blades rather than directly). Otherwise there were a couple of Marine Trent engines for the US's Littoral Combat Ship, EJ200s for Eurofighter, new build Adour engines and few helicopter engines.
Finally we had a tour around one of the engine test beds. It was initially built for testing the Olympus but now its used to test the finished EJ200 engines. There was one on the stand so we got to go up close and have a look around it. We were about to go when one of the technicians came in and said that they were about to do a test. If nothing else, the trip was worth it to see an EJ200 in full reheat from not very far away.
Firstly we had a talk from one of the engineers leading the Lift-Fan system for the Joint Strike Fighter. He gave us a brief overview and then went down in levels of details to give us more of picture of what his team was working on. They're having rather severe problems and overall it did more to convince me that a PCB engine with thrust vectoring is a much simpler and safer idea. For the JSF option, there is an aft mounted engine and a drive shaft forwards to a clutch, gearbox and a contra-rotating liftfan. The engine thrust mounts are at the back and the lift fan is fixed at the front. As the engine heats up during operation there is considerable stress imposed on the drive shaft and clutch. Both are critical systems for VTOL flight and so very few failures can be tolerated. Thats where the problems come in.
After this we had a short tour around the factory floor where they are making engines. It was quite interesting for me personally as they're vertically mounted and made up in modules. For non-defence there was EFE (Environmentally Friendly Engine) being made up which is due to go on tests next year to test new technologies. The main aim is for reduced emissions and greater efficiency through higher turbine temperatures, it was initially aimed at a more active cooling system for the turbine blades but this seems not to be possible. (HP air bled off the compressor, cooled and then going through the turbine blades rather than directly). Otherwise there were a couple of Marine Trent engines for the US's Littoral Combat Ship, EJ200s for Eurofighter, new build Adour engines and few helicopter engines.
Finally we had a tour around one of the engine test beds. It was initially built for testing the Olympus but now its used to test the finished EJ200 engines. There was one on the stand so we got to go up close and have a look around it. We were about to go when one of the technicians came in and said that they were about to do a test. If nothing else, the trip was worth it to see an EJ200 in full reheat from not very far away.