I read that when RR looked at open rotors they looked at the Allison experience (they took over Allison who had worked with P&W on the propfan), and weren't very impressed with their attempts at noise attenuation. Specifically, making the rear rotor smaller than the front makes a big difference....Jump to post
The 777 flies in the same flight altitude regime as all other large jet powered passenger airplanes, about FL280 to FL410. The fact that the heavier -300ER on a 14hr flight may stay at FL280-320 for a bit longer than, say, an A380 or 787, has minimal impact on turbulence, the worst weather related ...Jump to post
In terms of noise the A343 and A346 are completely different aircraft. The A343 is like sitting in a room with a lot of teenage girls drying their hair. On the A346 I was waiting for the engines to spool up at takeoff, but we just surged forward with little extra noise. A fabulously quiet and comfor...Jump to post
My guess would be that the MT30 does not need a reduction gear at all. To just make electricity (which I think is how most of these ships are actually driven when powered by gas turbines) I don't think you need a gearbox, but I'm happy to be corrected about this. For a ship with a propeller driven ...Jump to post
They should call the lowest class 'Scum class' to encourage people to upgrade.Jump to post
What is really remarkable is that all companies have problems with products - Rolls with the RB211, GE with the initial GE90, Airbus with the A380 and Boeing with the 787. But all these companies learnt. They weren't serial failures. Pratt on the other hand, one failure after another. They have lear...Jump to post
Imagine how many food mixers that could power. Dinner for thousands ready in seconds. GE very quiet on gears. P&W very quiet on a widebody GTF. Could RR have a jump on both come the next generation of widebody engines? I'm also intrigued about P&W's patents. Gearbox's have been around foreve...Jump to post
ikolkyo wrote:kurtverbose wrote:ConcordeAlpha wrote:XWB stands for Extra Wide Body.
When have RR stated that XWB stands for Extra Wide Body for it's engine?
You are over thinking it.... A350XWB - Trent XWB...... Pretty simple.
When have RR stated that XWB stands for Extra Wide Body for it's engine? RR haven't said it, it's just that logically XWB stands for extra wide body. Airbus A350 XWB - XWB stands for extra wide body. I wrote what XWB stands for in the opening post. You've not taken us any further forward than an as...Jump to post
In case it matters, the aircraft type of interest is DC3. When a piston engine is replaced by a gas turbine you notice the engine installation is a lot further forward. This is because, as has been stated, the gas turbine will be a lot lighter. The twin wasp engines in a DC3 weigh about 600kg each....Jump to post
All I hear is it will be the 'standard build'. I don't know if previous versions continue to be available. I don't know about 75% new parts. The Intermediate compressor is new - 'rising line' as in the XWB. The HP has blisks on the first 3 stages. I think it also has reprofiled compressor blades. I ...Jump to post
Why don't they have deployable blast doors like on aircraft carriers, then people could use the beach without the excitement of being killed?Jump to post
The quote was about the A350 had become to capable for regional use to be considered, to back up that the A350-1000 was not capable enough Thank you mjoelnir. I didn't think the contradiction needed explaining but apparently it did. Before anything changed the -1000 was perfect for EK's 777-300 rep...Jump to post
Why do you continually quote things that you say backs up your case when they clearly don't? I don't see a problem with the quote and his comment... The quote was about the A350 had become to capable for regional use to be considered, to back up that the A350-1000 was not capable enough Thank you m...Jump to post
This is exactly right. I would add that EK was specifically concerned with the A350 covering long range 77W missions from DXB where summer temps can go over 120 degrees. They have expressed a similar concern regarding the 787-10.... (I.e. maybe it's "underpowered"). Can an A350k fly a 700...Jump to post
EK said at the time of the cancellation of the A350 order that they felt the A350 was under-powered for their needs and did not have the payload capability of the 777X. I'd like to see a source for that because I think it's rubbish? The original A350 order was for regional routes. Emirates backed o...Jump to post
A bit of research and I found a flight profile on this website: - http://www.blodtandsmidigt.com/concordeprofiles.html It doesn't say the route or give weights but it's a +3.5hr flight so must be at or near MTOW. Concorde goes supersonic within 20 mins of takeoff, and is at mach 2 30 mins after take...Jump to post
At 25-45k lbf thrust the UltraFan concept is more a 757-sized engine and would not be suitable for the A330. I know you keep saying that ultrafan will only go up to 45k, but it's just a technology demonstrator for an architecture for all thrust classes. RR have been very clear that this is their fu...Jump to post
BA will place a top up A380 order so they can get all their customers currently stranded at LHR/LGW to their destinations.Jump to post
As for some complaints made about the sources I used....try Steven Udvar-Hazy of Air Lease who is without question one of the most respected men in aviation. His company has made big purchases of both the 787-9 and 787-10 as well as the A350. He says point blank (as the seeking alpha link I posted ...Jump to post
moo wrote:had his sentence doubled from 4.5 years to 9.5 years
TAP reporting they expect theirs in the first half of 2018, but it could clip to third quarter.
https://www.flightglobal.com/news/artic ... to-437522/
WHY would an airline choose an aircraft with a 50% higher fuel burn. So there's a linear relationship between fuel burn and number of engines? Many opertators chose the A340 instead of the MD11 - presumably they didn't mind the extra 1/3 higher fuel burn? That has been shown not to be as simple as ...Jump to post
PDX88 wrote:WHY would an airline choose an aircraft with a 50% higher fuel burn.
Looking at those numbers they still have work to be done. They were aiming for 25% reduction in block fuel per seat, the 77W nominal seat count when making that statement was 365 seats, and the A350-1000 350 seats. I work that out to be 290 kg/seat for the 77W and 224 kg/seat for the A350-1000, mea...Jump to post
Some cabin photos of the A350-1000 Early Long Flight: https://twitter.com/Airbus/status/863018187620798466 The high res version of the cockpit photo offers some interesting details- 4 hrs into the flight the aircraft has burnt 33t of fuel, has climbed to fl350, cruising at mach .854 and burning 6.8...Jump to post
There is a correlation between fuel price and number of engines. Bristol Brabazon, Saunders Roe Princess, even the Dornier DoX - fuel was very cheap. You can bet that if fuel gets cheaper not only will the A350 become 4 engined, but they'll be bolting extra engines onto many aircraft just for the sh...Jump to post
This A380 115 cap - is there no oportunity to trade 777's with A380's?Jump to post
speedbored wrote:For some reason, this thread made me think of this:
http://www.bbc.co.uk/news/av/uk-england ... -takes-off
Remebering the RR story, even with almost perfect efficiency of 99% for the gear it is still a huge amount of heat, 100kW-1MW range. Keep in mind how much MW power an engine has. This was the quote , from Professor Ric Parker, director of research and technology at Rolls Royce: - "Our first ge...Jump to post
Pratt invested how long in figuring out the cooling of the gearbox lightsaber, why is gearbox cooling such an issue? I've also seen quotes from RR engineers say that's a difficult issue. There's a big fan pumping huge amounts of air around the engine, and warming it up a little with a gearbox coole...Jump to post