STOVL or alternative

Even before reading "F-35: Out of Altitude, Airspeed, and Ideas — But Never Money | Battleland | TIME.com" today in #1086 in the US military news thread I was thinking about starting this thread.

There have been many VTOL, V/STOL and STOVL experimental jet aircraft but only two have been introduced into service: the Soviet Yak-38 and the Harrier family. Only the last have been produced in considerable quantity and used by military services of several countries. But are they really useful? Yes, the RN was able to use jet fighter-bombers from small flattops, initially called through-deck cruisers. And yes, the US Marines can use jets from large flattops that for political reasons cannot have arresting gear, cats or ski ramps. But don't try to use them in terrain much above sea level. A Chinese STOVL jet would be useless in Tibet.
Building kilometers long runways isn't very attractive either, certainly not when you are in a hurry. But a shorter steel covered runway ending in a steel reinforced ski ramp can be built in a day on reasonable soil, complete with arresting gear. A fighter-bomber with a long-legged tail wheel fit for use from a ski ramp equipped carrier but with large wheels for use on softer surfaces can be accommodated, the runway length being calculated for the ambient air temperature and density. This aircraft would not be compromised in the way Harrier and F-35 are.
Have I missed something? Is there anything useful the STOVL jet can do that my STOL jet can't?

^^^ Are suggesting using the likes of J-15 and carrier deck layout for Tibet environment? (with arresters and all)

I still think a traditional air field is easier and less complicated to maintain and repair.

delft, just for understanding since I'm a little confused. When you're talking about that tailweel for a plane, are you infact suggesting a "reversed tricycle landing gear" layout? Two main wheels in the front and another one in the back?
That would pretty much require a completely different aircraft layout, I assume. Not like all the other designs around were the center of gravity is somewhat in the back were the engines and all that suff are, but having all that toward the front of the plane to be supported by the main weels, with just a hoist arm in the back for control surfaces. Being reminiscent of WWII era planes.

Scratch said:

delft, just for understanding since I'm a little confused. When you're talking about that tailweel for a plane, are you infact suggesting a "reversed tricycle landing gear" layout? Two main wheels in the front and another one in the back?
That would pretty much require a completely different aircraft layout, I assume. Not like all the other designs around were the center of gravity is somewhat in the back were the engines and all that suff are, but having all that toward the front of the plane to be supported by the main weels, with just a hoist arm in the back for control surfaces. Being reminiscent of WWII era planes.

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It resembles indeed a reverse tricycle gear, but with this refinement that for take off from an ordinary runway rotation is achieved by retracting the tail wheel halfway. I might claim it as my own invention as nearly everyone will have forgotten, if they ever knew it, that a patent was taken out by a British inventor about forty years ago and described at the time in Aeronautical Journal. ( I wonder how the undercarriage of the Meta-Sokol, a Czecho-Slovak light aircraft of fifty years ago, functioned. It looked similar and might have been the inspiration for the inventor, whose name I have forgotten. )
One of the main advantages of the nose wheel u/c was that with the main wheels abaft the center of gravity unequal braking on the main wheels didn't lead as easily to a ground loop. This can now be prevented by the automatic braking system. The other main advantage, better view for the pilot while on the ground, is achieved with this system by having a long legged tail wheel.
By transferring a lot of the STOL installation from the aircraft to the runway the aircraft can be much lighter and its development, even if you try to provide three versions, for air force, navy and marine corps, will cost much less in time and money.

delft said:

It resembles indeed a reverse tricycle gear, but with this refinement that for take off from an ordinary runway rotation is achieved by retracting the tail wheel halfway. I might claim it as my own invention as nearly everyone will have forgotten, if they ever knew it, that a patent was taken out by a British inventor about forty years ago and described at the time in Aeronautical Journal. ( I wonder how the undercarriage of the Meta-Sokol, a Czecho-Slovak light aircraft of fifty years ago, functioned. It looked similar and might have been the inspiration for the inventor, whose name I have forgotten. )
One of the main advantages of the nose wheel u/c was that with the main wheels abaft the center of gravity unequal braking on the main wheels didn't lead as easily to a ground loop. This can now be prevented by the automatic braking system. The other main advantage, better view for the pilot while on the ground, is achieved with this system by having a long legged tail wheel.
By transferring a lot of the STOL installation from the aircraft to the runway the aircraft can be much lighter and its development, even if you try to provide three versions, for air force, navy and marine corps, will cost much less in time and money.

Click to expand...

but how those reverse tricycle gear would perform in jet take off ? you know the reason they choose nose wheel was because is very dangerous to take off and landing reverse tricycle gear with jet engine ?

delft said:

It resembles indeed a reverse tricycle gear, but with this refinement that for take off from an ordinary runway rotation is achieved by retracting the tail wheel halfway. I might claim it as my own invention as nearly everyone will have forgotten, if they ever knew it, that a patent was taken out by a British inventor about forty years ago and described at the time in Aeronautical Journal. ( I wonder how the undercarriage of the Meta-Sokol, a Czecho-Slovak light aircraft of fifty years ago, functioned. It looked similar and might have been the inspiration for the inventor, whose name I have forgotten. )
One of the main advantages of the nose wheel u/c was that with the main wheels abaft the center of gravity unequal braking on the main wheels didn't lead as easily to a ground loop. This can now be prevented by the automatic braking system. The other main advantage, better view for the pilot while on the ground, is achieved with this system by having a long legged tail wheel.
By transferring a lot of the STOL installation from the aircraft to the runway the aircraft can be much lighter and its development, even if you try to provide three versions, for air force, navy and marine corps, will cost much less in time and money.

Click to expand...

The problem is not with rotation.
The problem is the lift.

airplane tails are sized such that long before end of the runway, and well below your rotation speed, you would typically have enough tail power to rotate a/c nose. high in air. (i.e. like in a Vmu test)

the problem is at those airspeed your airplane's wings don't have enough lift to loft you up.

yes, airplane that don't have rotation power can use what you described to help. but typically those airplanes have extensive leadingedge and trailing edge devices and can generate enough lift at ridiculous high alphas with out issue.

once we are talking about fighters the requirement of high lowspeed lift and high speed cruise goes against each other directly in the wing design.

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for airplanes that don't need absolute VTOL but wants STOL, I suggest look at upper surface blowing, especially for support type of aircraft. that;s a good way to squeeze field performance out of a normal configure aircraft with out too much penalties.

blacklist said:

but how those reverse tricycle gear would perform in jet take off ? you know the reason they choose nose wheel was because is very dangerous to take off and landing reverse tricycle gear with jet engine ?

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Several of the first jet aircraft had tail wheels, such as prototypes of Me-262 and much later, the Supermarine Attacker. I know that to lift the tail during take off the pilot of the Me-262 prototypes had to actuate the brakes for a very short time. And after landing you have a miserable view to the sides of the runway.
The proposed landing gear provides a near horizontal fuselage attitude until rotation. After landing the tail wheel leg would be further extended to again provide a good view to the pilot.

---------- Post added at 10:39 PM ---------- Previous post was at 09:54 PM ----------

i.e. said:

The problem is not with rotation.
The problem is the lift.

airplane tails are sized such that long before end of the runway, and well below your rotation speed, you would typically have enough tail power to rotate a/c nose. high in air. (i.e. like in a Vmu test)

the problem is at those airspeed your airplane's wings don't have enough lift to loft you up.

yes, airplane that don't have rotation power can use what you described to help. but typically those airplanes have extensive leadingedge and trailing edge devices and can generate enough lift at ridiculous high alphas with out issue.

once we are talking about fighters the requirement of high lowspeed lift and high speed cruise goes against each other directly in the wing design.

---

for airplanes that don't need absolute VTOL but wants STOL, I suggest look at upper surface blowing, especially for support type of aircraft. that;s a good way to squeeze field performance out of a normal configure aircraft with out too much penalties.

Click to expand...

There are many conditions that have to be fulfilled by a horizontal tail plane. Lifting the center of gravity in front of the main wheels in an aircraft with a nose wheel is just one of them. With the alternative undercarriage you avoid the increase in drag that accompanies that introduction to rotation.

I was specifically looking for an alternative configuration for a fighter-bomber like F-35. I consider the parallel development of three fighter-bombers that greatly resemble each other but of which one can land vertically, at least at sea level, to be madness, just as indeed described in the Time article. And the huge increases in development time and cost prove the point.
If you want to improvise a base for such a fighter-bomber you need a load of equipment that will likely include a bulldozer and a grader as well as lots of fuel, ordnance &c. By providing a steel frame sunk into the earth at the end of the runway, filling it with dirt and covering it with steel plates you can save greatly on the length of the runway and on building time. It will also be easier to find space for your runway. The length of flat terrain might simply not be available for a long runway. Landings might be braked by parachute if arresting gear cannot immediately be provided.
By putting the stress of STOL operations on the ground you save a lot of weight and of production and maintenance effort for the aircraft.
Transport aircraft able to lug the same amount as a V-22 might well be designed to use the same type of runway and their use will be very much cheaper than that of V-22s.

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There are many conditions that have to be fulfilled by a horizontal tail plane. Lifting the center of gravity in front of the main wheels in an aircraft with a nose wheel is just one of them. With the alternative undercarriage you avoid the increase in drag that accompanies that introduction to rotation.

I was specifically looking for an alternative configuration for a fighter-bomber like F-35. I consider the parallel development of three fighter-bombers that greatly resemble each other but of which one can land vertically, at least at sea level, to be madness, just as indeed described in the Time article. And the huge increases in development time and cost prove the point.
If you want to improvise a base for such a fighter-bomber you need a load of equipment that will likely include a bulldozer and a grader as well as lots of fuel, ordnance &c. By providing a steel frame sunk into the earth at the end of the runway, filling it with dirt and covering it with steel plates you can save greatly on the length of the runway and on building time. It will also be easier to find space for your runway. The length of flat terrain might simply not be available for a long runway. Landings might be braked by parachute if arresting gear cannot immediately be provided.
By putting the stress of STOL operations on the ground you save a lot of weight and of production and maintenance effort for the aircraft.
Transport aircraft able to lug the same amount as a V-22 might well be designed to use the same type of runway and their use will be very much cheaper than that of V-22s.[/QUOTE]

Check out YC-14.

I know and work w/ some people who worked on that project.

it was basically able to have a stall speed around 50 kts. with ridiculous short field length.

On the VTOL vs STOL issue, I think a V-22 is again something different than the fighter-bomber. While the latter launches & returns to a prepared rundway, land- or seabased, the former actually has a real tactical need for it's capabilities. In combat scenarios, a V-22 will land at places were you can't just carve out a strip with a ramp at one end. So tactical transport , IMO, really has a need for vert lift capability in combination with high (plane like) speed.

Check out YC-14.

I know and work w/ some people who worked on that project.

it was basically able to have a stall speed around 50 kts. with ridiculous short field length.

Click to expand...

YC-14 was a beautiful concept. It was well picked up by Antonov, in An-72 and -74. But my interest in this thread is a fighter-bomber concept cheaper and more practical than F-35, and Yak-141 for that matter.
Btw there is also a concept similar to YC-14, not yet tried out AFAIK, with the engines on pylons above the leading edge of the wing to achieve the same take off and landing performance but with reduced drag in cruising flight.

---------- Post added at 08:56 PM ---------- Previous post was at 08:44 PM ----------

Scratch said:

On the VTOL vs STOL issue, I think a V-22 is again something different than the fighter-bomber. While the latter launches & returns to a prepared rundway, land- or seabased, the former actually has a real tactical need for it's capabilities. In combat scenarios, a V-22 will land at places were you can't just carve out a strip with a ramp at one end. So tactical transport , IMO, really has a need for vert lift capability in combination with high (plane like) speed.

Click to expand...

Your are right that V-22 has more functions that cannot all be fulfilled by a STOL transport. Just now I remember the Italian transport of a similar size, C-27. I should have mentioned that one instead of V-22.