Down the Rabbit Hole with Eviation's Alice

[redpoint5]

Originally Posted by samwichse

https://en.wikipedia.org/wiki/EGTS

How did you know about that?

I had the idea while waiting for a delayed tug to push us back from the gate. The whole process takes longer than necessary for such a routine task. Then we have to wait a moment for engines to start and come up to operating parameters before we get underway taxiing.

My other idea was autonomous ground robots that shuffle planes around, but then that would double the amount of driving traffic on the taxiway. It would eliminate accidents caused by encroaching on a runway in use though, and since it's automated, tighter time and spacing tolerances can be maintained.

[Piotrsko]

Only downside to robotic tugs is wing tip rash in crowded airports taxiways if someone didn't park in the correct bay. Talk about ruining your day because everything gets parked until the Feds reapprove the movement.

A lot of time waiting is for tower/ground approval to start. Heck, I even had to have permission at some airports.

[aerohead]

Originally Posted by redpoint5

How did you know about that?

I had the idea while waiting for a delayed tug to push us back from the gate. The whole process takes longer than necessary for such a routine task. Then we have to wait a moment for engines to start and come up to operating parameters before we get underway taxiing.

My other idea was autonomous ground robots that shuffle planes around, but then that would double the amount of driving traffic on the taxiway. It would eliminate accidents caused by encroaching on a runway in use though, and since it's automated, tighter time and spacing tolerances can be maintained.

Wait 'til a low-time student pilot lands on top of you during takeoff!
That happened to the Cherokee my brother flew out of Van Nuys Airport,California.He wasn't in the plane at the time,but it was the end of it,chewed rear-to-forward.Nut behind the yoke!

[Piotrsko]

Van nuys is just massive scary, any way you look at it.

[Joenavy85]

Originally Posted by Piotrsko

Not to disagree, but most everything in front of the props should be pretty much laminar unless it is a huge profile change.

I can see some turbulence at intersections and with the tip setup from vortice flow, and I wonder about the drive units operating in disturbed air but that will just reduce available thrust and not decrease drag.

I defer to your knowledge base as mine is mostly deduced from my aviation failures.

A "puller" prop gives you more efficient propeller operation due to it grabbing nice clean air. A "pusher" prop gives you lower propeller efficiency due to the relatively "dirty" air flow.

The airflow will be laminar for the most part, but when the air rejoins after going around the wing it isn't perfect.

A benefits of clean airflow around the fuselage on a "pusher" is more beneficial than the clean air being grabbed by a "puller". The downside is that, even when fly by wire, the control systems are more complex, as well as the balance being more difficult to fine tune.

[redpoint5]

Originally Posted by Piotrsko

Only downside to robotic tugs is wing tip rash in crowded airports taxiways if someone didn't park in the correct bay. Talk about ruining your day because everything gets parked until the Feds reapprove the movement.

A lot of time waiting is for tower/ground approval to start. Heck, I even had to have permission at some airports.

I was thinking in terms of large/busy airports. There'd be no rash if everything was automated. The tugs would know the dimensions of their aircraft, and know how to shuffle them around without collisions. Perhaps the tugs would do the taxi in too. That might be better than returning to the gate empty handed anyhow, as it reduces ground traffic.

The John Deere I drove had GPS steering. I had to make the figure-8 turns at the end of the rows, get within 18" of the upcoming row, then push a button to give control back over to the automation. Similar principles would apply. Tug needs the plane to be within a defined space, or it is going to refuse to play.

[freebeard]

Originally Posted by myself

It looks like all the air sees is high-efficiency airfoils and propellers sucking any detached airflow for lunch.

Joenavy85 — That was my point, the laminar flow can approach perfection, and the props are there as a backstop.

The wingtip nacelles are radiators first for cooling efficiency. The torque vectoring in yaw is just gravy.

Now all it needs is an electric tail wheel.

[euromodder]

Looks a lot like a pusher-variant of the Bugatti 100p

https://www.flitetest.com/articles/t...ime-here-s-why

If one of the tip-engines fail, asymmetric thrust errrrr..... push may well come an issue
Thats a big moment arm !

[freebeard]

It's not a blended body, but the Buggati was cool. I think of the Vought XF-5U. No fuselage at all, but it has the wingtips propellers.