VTO Skymaster
 

Frank Tushoph sent this along.
Parked at the Ramona, CA airport (RNM, or KRNM, if you prefer) is Skymaster that has had four "lawnmower" engines added aft of the wing (see Pix), apparently to allow VTO or VSTOL take offs. Anybody know anything about this experimental airplane?

Frank Tushoph

Another picture of this unusual airplane.

A view from the front.

As seen on TV
 

Formaly known as a "Sky'TORO'master", this unique aircraft provides verticle lift by "MOWtating" upward with the added "Briggs and Stratinental" deck mounted engines. The takeoff ability is greatly enhanced but don't forget the "LANDscaping" feature is also greatly improved. Very popular for unimproved airports that require a precise manicured surface. The engines rotate to provide the grass cutting feature as you back taxi for take-off. Quite popular in the upper midwest where frequent Skymaster enthusiast's gather for summer fly-ins.

Currently the "SkyTOROmaster" is grounded for an enexpected AD requirement to have the blades sharpened.

For more information go to:

www.hovermower.bs

Thanks, Herb. Until I saw your message, which I assume is in jest, this is what I had written:

"Akward, to say the least. I would guess that these "lawnmower engines" add substantially to drag, so cruise speed has to be reduced measurably. Does anyone know what's the purpose of these engines? If it's for STOL, how is it done?

Puzzled in Miami"

The owner is listed as "TURBO WING INTERNATIONAL"

The engines act as boundry layer suction devices, increasing the lift at relatively low airspeeds. They suck the air off the top of the wing, and direct it downwards. At the same time, the airflow over the bottom of the wing is enhanced, resulting in siginifcant reduction in takeoff requirements, especially on runways that pose a hazard to normal operations.

With the engines mounted aft of the wing, and cockpit , the pilot enjoys the added plusses of having great forward visibility. Helicopter pilots landing in snow find themselves in a veritable blizzard, caused by the down wash from the rotors. They litterally have to feel their way for the ground. This overcomes all those dificulties. In addition, with a low wing airplane, the snow would tend to blow around the wing, creating an Icing situation.

It's just perfect for those people who want to fly off of snow covered airports. Of course, that it is in California, near a beach, is of no consequence.

Of course, it is no longer a complex aircraft, since the flaps have been removed, to provide a scalloped edge on the trailing edge of the wing.

OKay. Which one of my legs is longer than the other? Somebody's got to be pulling it.

This is certainly an unusual aircraft, and a very unusual Skymaster.

If memory serves me correct (very suspect), the F-104 Starfighter used not bleed air, but intake air, but maybe bleed air, I don't know, to slow the landing speed. When the flaps were lowered, and you remember that the leading edge also lowered, (and on the ground they were covered because they were razor sharp) air was diverted from the engine to the wing, and stall speed went from 300+ knots to 235 knots. One of the many problems with the F-104 was that there was no back up system, so if the air diversion valve failed, suddenly you were stalled. And of course, in the early models, ejection was out the bottom.

So that leads me to believe they were, are, doing boundry layer control stuff with those aft engines.

Okay, so I looked it up. Just like when I was a kid, and we had encyclopedia britannica.

http://en.wikipedia.org/wiki/F-104_Starfighter

The F-104 did use boundry layer control, blowing bleed air over the flaps, to significantly reduce landing speed.

There were several airplanes developed with boundry layer control systems, all of them jets. One, the Hunting H.126, had a take off speed of 32 MPH.

My two cents worth, NASA did a whole bunch of boundery layer testing. And as it turns out, it's all about the airfoil and how it is constructed (visa ve, the DH-7, "dash seven", or even the -8 too, and the Predator UAV). Those aircraft all have such good laminar flow that the wing never really stops creating lift (and Predators crash alot because they don't stop flying during landing roll-outs).

So adding engines and getting rid of flaps on a Skymaster, not too practical. BUT, developing a new wing made of compossite material... equals better boundery control. And maybe even better speed and payload too. So who's ready to make new wings for Skymasters????? What a great STC idea.

What a great idea!!!
We can get rid of the wing spar AD too!!

Could you get rid of the wing spar AD if you put new wings on it??