Quad Tilt Rotor

[kitnut617]

Well I done a lot a thinking to this project, mainly because I have the picture of it as my desktop back ground pic so I see it everyday.

I've got a feeling the concept just isn't going to fly, by that I don't mean it couldn't fly, just that how it's arranged it won't work even though I think it looks super-cool.  I think there's a serious chance that the rear engines could suffer from hot exhaust ingestion even though the rear nacelles are set higher and further out.  You would only have to have a slight yaw or even a cross wind for the front engine exhaust to enter the rear engine intake, or even a quick pull-up would cause hot exhaust to enter the rear engines.  I think that this would have to have the engines grouped around the tail and now that the engines on the A400M has been sorted out, I think there's a source for a couple of big engines.  Of course, there always the likelyhood that there will be an American equivalent in the future.

My thinking now is leaning towards converting the wingtip engine nacelles into jut having gearboxes and a couple of CH-53 style engines on either side of the fin, so -----  does anyone have a pair of those 1/48 CH-53 engines lying around that they don't need, with the filters   

[Green Dragon]

I've been thinking exactly the same Kitnut, hot gas injestion looks highly likely but not a problem with gear boxes. Also toying with the original X-22 layout of ducted props/fans powered by engines grouped at the tail instead of using V-22 bits. Might incorporate some Chinook sponsons after seeing the QTR cutaway pic!
Afraid I haven't got any 1/48th CH-53 engines! I was thinking of doing the engines in a CH-46 style by scratch building the housing in the tail section with plasticard and putty and plonking a single tail fin on top of the new housing.

Paul Harrison

[frank2056]

Would hot gas ingestion be such a big deal? The exhaust from a turboprop turbine will be mostly "spent" by the time it leaves the exhaust and mixing into the much larger volume of cool air blasting by from the props. By the time that column gets to the rear engine, it won't be that hot. Also, an IR suppressor will cool the exhaust even more. I'd worry more about turbulent flow into the rear engines/props.

Where's Evan? He'd know.

I like the idea of fuselage mounted engines driving the props, though.

[rickshaw]

Cooling the exhaust will not put more oxygen back into it and that is the problem.  As I understand it, gas ingestion results in a flameout not because of its heat but because there isn't sufficient oxygen to sustain combustion.