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Comment by cyberferret | Hacker News Reader

I am sure the engineers who designed and built this aircraft know what they are doing, but as a pilot, I would be hesitant to fly this aircraft based on the very low level of forward visibility (especially when landing).

Also, the pusher prop concept was tested extensively many years ago, but seems to have disappeared off the radar of most aero engine manufacturers. I don't know the exact reasons, but I am presuming that they had problems with efficiency, or more likely issues with the blade tips reaching sonic velocity (which will be higher risk with this aircraft if it cruises at FL065).

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Really tiny 4k 60Hz cameras with surprisingly good quality are available now, I don't think it would be rocket science to integrate one into the nose and feed a low-latency view to flight deck monitors. Possibly intefrated with an overlay image for short range time of flight lidar to gauge distance to runway during landing.

A proper aircraft flare at the point of landing requires a fair bit of peripheral vision to judge sink rates etc. A camera tends to give you a flat picture without that advantage.

It's a workable solution, but most 'seat of the pants' pilots would eschew such things.

If this ends up being an airline aircraft, as opposed to a personal aircraft, that might not be a problem, at least business-wise.

I'd be reluctant to fly on anything of this level of redundancy where an electrical failure results in a 0/0 landing (or an abnormal that precludes the use of the system added to ensure normal landing visibility).

The Icon A5 uses a pusher prop.

We'll see what, if anything, becomes of the Terrafugia too.

Pusher props are fine for aircraft cruising, say, around FL020 and below.

But at higher altitudes, the speed of sound is considerably lower, and the radial velocity of the prop blade tips start to reach sonic velocity, with the corresponding significant increase in drag, thus requiring more torque to spin at constant RPM, resulting in decreased fuel efficiency.

The test bed pushers on commercial jets were a far shorter set of (more numerous) blades for that exact reason. This particular aircraft seems to have a standard sized propeller, with a greater blade length, and corresponding greater radial tip velocity.

> FL020 and below.

I'm assuming you meant FL200. (20000' MSL, not 2000' MSL.)

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