Either this is one of the biggest scams in history, or is it real?

[Fly Boomer]

11 hours ago, cliffy said:

Yes they are connected across the wing centerline if one engine fails

Still has density altitude issues just as any twin engine airplane on one engine  (KPGA)

As to the landings the propellers are designed to (as they say) "corn broom" when coming in contact with the runway landing in the forward thrust setting.  

The blades wear down much like a broom at the ends and the entire blade does not come apart upon contact. 

Doesn't sound like much fun, but it beats some of the alternatives.

[A64Pilot]

On 8/16/2023 at 10:27 PM, cliffy said:

Yes they are connected across the wing centerline if one engine fails

Still has density altitude issues just as any twin engine airplane on one engine  (KPGA)

As to the landings the propellers are designed to (as they say) "corn broom" when coming in contact with the runway landing in the forward thrust setting.  

The blades wear down much like a broom at the ends and the entire blade does not come apart upon contact. 

Never has happened and it’s extraordinarily unlikely it ever will, just like the AH-64 main driveshaft has a shear section that will shear in the event the main transmission seizes, never been tested and has never happened, but at least there is a plan.

For all I know you could feather an Osprey and land at 200 kts or something. The nacelles rotate on a jack screw that I’m pretty sure is hydraulically driven, I’ve been around one but never flew one or really dug into it.

I doubt they would autorotate very well though due to rotor size, in fact I bet due to not having a freewheeling unit they can’t autorotate at all.

The ring or something that was talked about is essentially a ducted fan type of thing, it works, sort of, but not as well as explained.

On boats it’s called a Kort nozzle https://en.wikipedia.org/wiki/Ducted_propeller

Primarily used on slow speed vessels and when prop protection is a big deal or things in the water like a life boat or tour boats to look at the Manatees and you see them on every Scuba scooter I’ve ever seen mostly to protect the diver but there is some performance increase, they operate pretty similarly to what winglets do on aircraft wings.

On an aircraft theoretically they could improve thrust on a smaller diameter prop, I say theoretically because to my knowledge it’s never been done, they just add more blades if needed, the “ring” would add weight and be subjected to the maximum centripetal forces and act as a gyroscope, which on a Quad copter as the rotor is not tilted may not be all that bad a thing I guess, unless of course they were fixed like on a boat then it’s just weight

[cliffy]

Battle damage might forego the ability to rotate to hover mode so a landing in fwd thrust mode "could" happen hence the ability to "corn broom" the prop blades

I can only guess at the landing speed but I would surmise 150 kts would do it due to weight , wing plane form and area.

Weight per Sq foot is probably lighter than say a Boeing due to the need to lift vertically so that in it self would lower the landing speed.

A Boeing does good at no flaps and about  190 kts over the fence  If we look at the V-22 with the engines acting as end plates and compare that to say a MU-2 with the tip tanks doing the same an MU-2 does good at 95 Kts no flap over the fence. Just doing some rough comparison.

[glbtrottr]

Blah blah blah type certificate blah.

I worked for the #1 stock of the decade in the 1990’s which appreciated 90,000 percent per the WSJ, September 1998.

We took positions on customer stock in more accounts than I can remember.

Archer? Pick a dozen.

Learn the term PUMP AND DUMP.

The FAA runs on slightly antiquated technology - the bureaucrats in it are often even more so. In this case, as they were in the 737/800 case, as they were in many manufacturers’ schemes to get things approved if only the proper inspector is hired….

…they are a willing tool in the pump and dump schemes of many an EVTOLs manufacturer.

A fool soon parts with his money.

[Pinecone]

On 8/19/2023 at 5:59 PM, A64Pilot said:

The ring or something that was talked about is essentially a ducted fan type of thing, it works, sort of, but not as well as explained.

On boats it’s called a Kort nozzle https://en.wikipedia.org/wiki/Ducted_propeller

Primarily used on slow speed vessels and when prop protection is a big deal or things in the water like a life boat or tour boats to look at the Manatees and you see them on every Scuba scooter I’ve ever seen mostly to protect the diver but there is some performance increase, they operate pretty similarly to what winglets do on aircraft wings.

No, there is a new prop, that looks like 2 props with the tips connected.  I will look for a picture.

[cliffy]

Its called the Sharrow Prop

It doe a a significant job of lowering the cavitation ( and noise) of a boat prop

It has some improved thrust also due to less cavitation

But the noise reduction is dramatic

[A64Pilot]

I was trying to find the picture of 2-6 cav’s aircraft that crashed in a brown out in Iraq. It’s really good to illustrate what happens when a blade contacts the ground.

Composite blades “corn broom” it’s just how they are made, they come apart, it’s not a design feature, it’s just what happens when composite hits the ground.

Although the AH-64’s blades are four section of titanium spars any one of which will keep the blade together to survive an ADA hit, they still come apart