J. Southworth
  • Member for 4 years, 2 months
  • Last seen more than 2 years ago
Why do most military aircraft use different engines than commercial aircraft?
6 votes

It isn't universally true that military and commercial aircraft use different engines. The military and commercial versions of the Boeing 707/C135 used similar engines as do the military and ...

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What measures prevent a military aircraft's weapons from being fired on the ground?
5 votes

The article quoted implies that there is a sensor in the F16 to detect when the undercarriage is lowered, which functions as a a gun safety switch, but there is presumably provision for overriding ...

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Are there any truly 'unrecoverable' situations?
5 votes

A stall at low altitude would be one unrecoverable situation, but hopefully the instructor would be alert enough to intervene in time to prevent this occurring. Spins are normally recoverable in light ...

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Why was the P-51 Mustang not adopted by the U.S. Navy?
5 votes

The US Navy didn't need the P51 because they had the F4U Corsair, which had comparable performance, was better suited to ground attack work, and was designed from the start with a tougher structure ...

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Why do the MiG-15 and MiG-17 have a split air intake in their noses?
4 votes

The two air intake ducts of the MiG 15 pass either side of the nosewheel box and the cockpit. The alternative configuration of having a single duct passing underneath the cockpit, as used in the A7 ...

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Would an area-ruled fuselage improve the MiG-15/17's performance?
4 votes

The shape of the fuselage MiG 15 and MiG 17 fighters resulted from the large diameter of the engine used, the Russian version of the Nene centrifugal turbojet. The "area rule" has more effect on the ...

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Are transport gliders used by modern armies?
4 votes

Glider assault landings during the Second World War proved inherently hazardous, more so than parachute drops, and crashes typically resulted in deaths and serious injuries among the personnel being ...

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Do fighter jets experience a reaction or recoil force upon firing a missile?
4 votes

In some early jet fighters such as the F94 Starfire, air to air unguided rockets were carried in launch tubes that were built into the aircraft structure and closed at the rear end. Launching the ...

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How did jet engine aircraft perform compared to the best reciprocating engine aircraft during WW2?
4 votes

The speed advantage of the Me262 gave it an advantage in combat over the piston engined aircraft used by the Allies, once German pilots had developed suitable tactics which exploited this advantage ...

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Why do airplanes use an axial flow jet engine instead of a more compact centrifugal jet engine?
3 votes

While a centrifugal compressor can acheive greater compression than a single compressor stage in an axial flow engine, the axial flow design allows for multiple compressor stages, achieving higher ...

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What is the procedure for a rejected Jet/Rocket Assisted Takeoff (J/RATO)?
3 votes

Once the rockets are ignited, it is basically too late to abort the takeoff, so the decision would have to be made before doing that. This is one reason why RATO is not used today as much as it used ...

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If a circling airplane (AC-130) fires a bullet how does the plane's trajectory alter the shell's flight path?
3 votes

When a projectile is fired from a gun in a fixed wing aircraft or helicopter in a direction perpendicular to the direction of flight, the airflow across the muzzle has an effect on the trajectory ...

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Is it possible to design a helicopter with fixed rotor blades only (no blade angle/flap/pitch)?
2 votes

Theoretically yes, you could build a full-size quadcopter with four fixed pitch rotors, and control it through independent variation of the rpm of each rotor. The power density now achievable in ...

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Can a bird strike destroy the stealth capability of F-35?
2 votes

There have been numerous losses of military aircraft as a result of bird strikes, including multi-engined types. If a bird can cause serious damage, this suggests that an intentional collision with a ...

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How to recognize the horizontal winglet in the Horten design, or the experimental glider in this video?
2 votes

Looking at the picture of the glider, the orientation of the hinges indicates that the winglets should provide directional control, replacing the rudder as well as the ailerons. The original Horten ...

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Why do drones look different from common airplanes?
2 votes

The most obvious difference between a drone or UAV or UCAV, and a manned aircraft is that it has no pilot, and therefore no cockpit structure. In practical terms this means that the minimum cross ...

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Is there currently any heat shielding and paint for speeds of up to Mach 6?
2 votes

The SR72 is not a variant of the Lockheed SR71 but an entirely new, unmanned high speed reconnaissance and strike vehicle being proposed by Lockheed Martin. The designation is obviously intended to ...

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Why did the RAF buy the F-35B model and not the A model
2 votes

The MOD originally planned to buy the B version, then changed their minds and wanted the C version, then changed their minds again and reverted to the B version when the cost of converting the Queen ...

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How can I determine specific heats of gases for turbojet engine calculations?
2 votes

Do you have a copy of the book Gas Turbine Theory by H. Cohen, G.F.C. Rogers and H.I.H. Saravanamuttoo? You may well find the answers in there I think.

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Could a SR-71 be shot down today?
2 votes

The Lockheed A12, the predecessor to the SR71, operated by the CIA in photo reconnaissance missions over North Vietnam could sustain a maximum altitude of 95,000 ft and Mach 3.5. None were shot down, ...

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Could modern military aircraft be retrofitted to work with alternative fuels instead of kerosene?
2 votes

In the 1950s, the US military were very interested in using high energy synthetic ethyl borane fuels, collectively known as "zip fuel", in aviation turbine engines. The XB70 Valkyrie was intended to ...

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What is the difference in VTOL technology between British Aerospace Harrier II and F-35B?
2 votes

In the Harrier, the bypass air from the large diameter low pressure compressor of the Pegasus engine is ducted through the front pair of nozzles while the remaining gas output from the engine passes ...

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Why don't combat aircraft have rear-facing weapons?
2 votes

Some tactical fighter aircraft can be armed with rearward firing weapons. The Russian SPPU-6 gun pod containing the six barrel GSh 6-23 cannon can be mounted on a pylon facing either forwards or ...

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Pros and cons of a pull-push propeller configuration
2 votes

A push-pull arrangement with a "puller" propellor in front of a "pusher" can give rise to problems of aerodynamic interference with the rear propellor at higher power levels, this was a problem with ...

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Why are movable rocket thrusters not used in airplanes?
2 votes

The advantage of rocket thrusters over conventional aerodynamic control surfaces is that they work in space. This is not a factor for commercial airliners, but some research aircraft designed for very ...

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How effective was WWII bombers self defense anti-air armament?
2 votes

The question of the effectiveness of bomber armament during the Second World War has to be assessed in the context of the bombing tactics used rather than in isolation. The tactics used by the USAAF ...

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Why don't single-engine jets suffer severe gyroscopic effects?
2 votes

The torque produced by piston engines was also an issue for military aircraft in the first and second world wars, particularly when engines were operating at full power, as during take-off when it ...

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How can a modified ramjet produce static thrust without a turbine?
2 votes

Another way to realise a liquid fuel ramrocket engine, in theory, would be to incorporate the rocket motor into the ramjet air intake centerbody. As the aircraft approached ramjet operating speed, the ...

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How does a combat aircraft handle the recoil force of a mounted gun?
2 votes

The firing of a forward firing cannon can generate thousands of pounds of reverse thrust. The use of shock absorbers in the gun mounting has the effect of reducing the peak recoil forces which might ...

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Will manned aircraft have to defend ground targets against unmanned aircraft in the future?
2 votes

Some advantages of UCAVs over manned aircraft in the strike role: The enemy doesn't gain hostages when they get shot down over enemy territory The numbers that can be deployed are limited by the rate ...

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