Call me stupid. A wing engine AFAIK is not limited in size with regard to "above"/"below". Obvious limit is placement cannot be closer than radius.
Call me stupid. A wing engine AFAIK is not limited in size with regard to "above"/"below". Obvious limit is placement cannot be closer than radius.
Hi,
They had to move the 737 Max engines forward and up to avoid the larger fans hitting the ground, changing the center of gravity which apparently is why the failed software was added (Causing two crashes).
cheers, Jamie
>
Moving the engine(s) up causes two effects, both undesirable:
a) the thrust line moves up, causing adverse pitch (nose up/down) changes along with thrust changes,
b) the center of gravity moves up, causing less stability on both pitch and roll axes.
I have flown one high-engine aircraft (Lake Buccaneer), and it ws a challenge compared to other planes of similar size. I did not like.
-- -TV
Hi,
That Lake Buccaneer looks like an extreme example, I can imagine that would not be good, the ratio of airplane length to the engine arm length is too low.
cheers, Jamie
Nah, too much complexity/expense/failure modes.
Go with VTOL passenger planes. No runways needed at all.
(ahem)
Dr. HotSalt
Just a *little* more fuel, less lift capacity, lower reliability, and
*slightly* higher operating costs. Yeah, that'll work. Airlines are rolling in cash.
It looks like airbus is already working on a new jet concept that will work for water landings quite easily. The wing is on top and they use hybrid electric fans, so it could more easily be made fairly immune to water/salt, as there is no jet engine combustion chamber to rust etc.
Also the battery could be a "flow battery" and the jets could refuel while landing/taking off by scooping up some of the liquid runway. The discharged flow battery liquids can be dumped by the planes when they land at the end up of the runway to be recharged.
Here is an old idea of floating airports, unfortunately they didn't realize they can land right in the water instead:
cheers, Jamie
Saltwater on thin ali aircraft... a match made to descend from heaven.
NT
Yeah, Popular mechanics. There's a top-notch technical journal with a long history of predicting the future.
You're nuts.
Yeah, another of Popular Mechanic's great prognostications. Keep believing in the tooth fairy, moron.
Hi,
I guess if you can't think laterally the idea would seem insane, however consider how batteries are being considered for grid storage of energy, and also how flow batteries are one of the most economical large scale types of batteries. Why not use the airport as a giant flow battery for the nearby city as well as for aircraft? The liquids used could be selected for energy density as well as freezing point.
cheers, Jamie
Hi,
Idea has been updated to electric powered composite aircraft with low freezing point flow battery liquid runways.
cheers, Jamie
No, moron, it only seems insane because IT IS insane.
Idiot.
Hi,
Based on your concise feedback I think a simpler idea is to use a flow battery with lithium bromate aqueous solution as the runway, and refill the aircraft with liquid hydrogen as well as refill with the runway liquid.
"flow battery employing H2 as the fuel and one or more of highly soluble halate salts (such as 50 % w/w LiBrO3 aq.) as the oxidant presents a viable opportunity as a power source for fully electric vehicles which meets the specific energy, specific power, energy efficiency, cost, safety, and refill time requirements. We further disclose a process of regeneration of the fuel and the oxidant from the discharged halide salt and water using electric (or solar) energy as the only input and generating no chemical waste."
From wikipedia:
This type of battery has 750 Wh/Kg energy density which is above the 500 Wh/Kg mentioned as minimum for aircraft:
"Our estimates suggest a regional aircraft would need a battery with a gravimetric density of 500 Wh/kg at the pack level to achieve a range comparable to today?s levels"
If lithium chlorate aqueous airport runways could be safe, the energy density is 1400 Wh/Kg from the same wikipedia page.
I couldn't find the freezing point of aqueous solutions of aqueous lithium bromate or lithium chlorate, but they should be somewhat below
0C.Requiring liquid hydrogen for this system is a deal breaker I think, but that may be the only type of flow battery with high enough energy density.
cheers, Jamie
not by sensible people, unless they're optimistic about profiting from it
why don't you answer that yourself, it's not a hard question.
NT
I guess you are referring to having an uncovered airport sized pool of reactive and likely toxic chemicals. You work for the EPA?
cheers, Jamie
not me
not me. Not Jamie either I'd bet.
Hi,
Yes but not because I am ok with pollution. The EPA is ok with far worse pollution than my idea, ie. internal combustion engines and factories etc create particulate air pollution that has far reaching effects that are mostly ignored.
cheers, Jamie
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