Russia’s war / invasion of Ukraine got me thinking.
I remember reading years ago, that modern heat seeking missiles are of no use in targeting general aviation aircraft, as their engines don’t give off enough heat for the missiles to lock onto.
So could GA aircraft have a useful role in a military engagement? They can operate high enough to avoid munitions, are too cold for heat seeking missiles and slow enough that the speed of supersonic fighters is of no advantage against them?
To be clear I’m not thinking of air defence. Rather perhaps a resonance or transport role?
How would a modern fighter tackle a GA aircraft? Presumably with guns, but GAs relative slow speed would make for big speed differential giving less time to aim accurately and at such slow speeds modern fighters won’t be very manoeuvrable as they will be close to their stall, while the GA aircraft will be very manoeuvrable.
It’s just an idle thought. I’m sure there are easy ways for a modern fighter to tackle a GA aircraft, and easily answered by someone with knowledge of them. I just wondered if so much effort has been put into attacking high speed, high performance aircraft that it’s made slow speed aircraft harder to target?
Can anyone with knowledge of such aircraft and systems set me straight?
Ukraine is using Turkish Bayraktar TB2 drones with great success. I’d venture a guess it’s at least an order of magnitude more efficient than MiG-29 in terms of cost per hit. Other than being unmanned, it’s a typical GA aircraft: Rotax 912 engine, 650 kg MTOW, 150 kg payload (reconnaissance and/or weapons), 12 m wingspan, 70 kt cruising speed…
20 years ago, Tamil Tigers in Sri Lanka used Czech Zlin 143.
During WWII, Soviets used U-2 (a.k.a. Polikarpov Po-2) wooden biplane trainers (1400 kg MTOW) as ground attack planes and night bombers. The usual bombing tactics was to glide with an engine off or at idle, approaching the target as low as 150 ft AGL. The most famous U-2 unit was an all-female air regiment affectionately known as “Night witches”.
I remember reading years ago, that modern heat seeking missiles are of no use in targeting general aviation aircraft, as their engines don’t give off enough heat for the missiles to lock onto.
That’s not true. I was trained on a system similar to Stinger produced in former Yugoslavia (Strela 2M, based on improved Soviet technology) and we were able to get lock on anything from C172 to jets.
All the US Army L-Birds, O-birds (Cessna Bird Dog) etc up to the OV-10 Bronco were derived from GA aircraft and utilized their maneuverability to good effect. Cessna O-2s (337 Skymaster derivatives) were used in combat up the 1980s, latterly in El Salvador.
Many will be aware of the use of armed, Swedish produced MFI-9s in Biafra, the same type produced in Germany as the Bölkow Junior. They flew unbelievably low to avoid ground fire and destroy aircraft on the ground, with some success. I think the pilots were exceptionally skilled.
Re UAVs in combat, Rotax powered UAVs were first armed with Hellfire air-to-ground missiles for use in an attack role well over 20 years ago, typically flying high in the Air Force role. Some history here. The prototype is in the Smithsonian Air & Space museum. Diesel powered variants of a similar airframe fly to this day in Army service.
Emir wrote:
That’s not true. I was trained on a system similar to Stinger produced in former Yugoslavia (Strela 2M, based on improved Soviet technology) and we were able to get lock on anything from C172 to jets.
Interesting. That would seem to put a real dampener on using GA in a war zone!
RSAF (Saudia) shoots smaller-than-GA UAVs with AMRAAMs from F15.
Not cost efficient but they definitely can get a lock on a GA aircraft. And don’t forget SAMs.
Not to mention FLIR tracking that is on most modern fighters.
Forget it 
Modern missiles don’t look for heat but for a specific IR image with a very low threshold.
Also, every fighter has an air to air cannon which would shoot down a GA a/c with just a few rounds.
The advantage of a small GA airplane compared to a jet is a much more trivial one: A stinger or similar rocket is about 100k per shot.
Therefore the economic balance (cost for attacker vs. cost for defender) is much closer to 1:1 than if a a 1bn+ F-35 is shot down with the same weapon. Same is true if you have to burn tons of fuel for an intercept mission on a cheap SEP.
GA aircraft, being very slow, would be vulnerable to old-fashioned anti-aircraft artillery and not many GA types can get high enough to be out of reach.
Air-to-air, cannon/guns obviously, and if heat-seeking missiles have difficulty then I’m sure radar-guided ones won’t.
Missiles are much more agile than a GA aircraft. The intercept capability limitation of a heat seeking missile is based on the rate at which the angle (seen by the missile) changes, at short range i.e. shortly before the intercept. A supersonic target turning at 9G will be moving across the missile’s field of view quite fast. A GA target pulling say 3G at 150kt will be hardly moving, relatively.
However, a modern missile probably tries to aim ahead of the target; this current Ukraine video shows it quite well
Look at the speed of that thing. Admittedly that is at a close range but in a GA plane you would hardly have a chance to move.
Radar guided missiles are a much bigger thing and are more or less fixed or vehicle-mounted; you can’t carry them around 
