Airbus and Rolls-Royce hit eject on hybrid-electric airliner testbed

[Piotrsko]

I dunno, seal it up pretty good, and use a submarine system to remove C02 and you could get away with a fairly small tank of O2. The tanks on the space station aren't that big. The pilots have to breathe their own separate air anyways, by law

[cRiPpLe_rOoStEr]

Originally Posted by Tahoe_Hybrid

Air can be stored quite effectively in bottles when the ICE is running

Sure, but it also adds some weight and complexity. Holding compressed air for the engine starters is a whole different matter than having to store enough air to keep an airliner pressurized while cruising only on the electric motors or gliding. Considering some earlier pressurized aircraft had engine-driven compressors instead of resorting to air bleeding from the engine's compressors, maybe an accessory compressor driven by an electric motor shouldn't be so out of question. But anyway, it wouldn't surprise me if an electric motor becomes a viable replacement for both the reduction gear (when applied) and the accessory gearbox of an airliner engine.

[redpoint5]

Originally Posted by JSH

I made housings for the shuttle high-pressure fuel turbopumps at my first job out of school. 71,140 hp shaft horsepower from a pump a little bigger than a Chevy big block.

That is crazy... a fuel pump that is 71,140 horsepower. It must be moving a swimming pool amount of fuel in a minute or something.

Originally Posted by cRiPpLe_rOoStEr

Sure, but it also adds some weight and complexity. Holding compressed air for the engine starters is a whole different matter than having to store enough air to keep an airliner pressurized while cruising only on the electric motors or gliding. Considering some earlier pressurized aircraft had engine-driven compressors instead of resorting to air bleeding from the engine's compressors, maybe an accessory compressor driven by an electric motor shouldn't be so out of question. But anyway, it wouldn't surprise me if an electric motor becomes a viable replacement for both the reduction gear (when applied) and the accessory gearbox of an airliner engine.

It would be pretty simple to have an inlet on a high pressure surface of the aircraft provide the higher pressure.

[freebeard]

It must be moving a swimming pool amount of fuel in a minute or something

A skyscraper full of fuel and oxidizer in 4 minutes. See https://youtu.be/LbH1ZDImaI8?t=22 for a diagram of the competing open cycle, closed cycle and full flow variants.

[JSH]

Originally Posted by redpoint5

That is crazy... a fuel pump that is 71,140 horsepower. It must be moving a swimming pool amount of fuel in a minute or something.

The Shuttle burned 535,000 gallons of liquid fuel in a little less than 9 minutes.

According to NASA, each pump (there were 3) would drain a swimming pool in 28 seconds. https://www.nasa.gov/centers/marshal...r/ssme_11.html

The High Pressure Pump (HPLT) was fed by a Low Pressure Pump (LPLT) The LPLT pressurized the fuel to 275 psi and then HPLT increased that to 6515 psi.

Full story here: https://spaceflight.nasa.gov/shuttle...p/engines.html

[cRiPpLe_rOoStEr]

Originally Posted by redpoint5

It would be pretty simple to have an inlet on a high pressure surface of the aircraft provide the higher pressure.

You mean some sort of ram-air? Doesn't seem so easy to increase air pressure to the same extent now applied to the combined HVAC and pressurizing system of modern airliners.