- Yes
- No
Introduction & History
In the late 1950s the first of a new generation of aircraft were taking flight, out of fantasy and into reality came the P.1127, the first ever successful VSTOL prototype. This P.1127 proved many people wrong, even going so far as landing on ships in temperate climates to out- performing the Hawker hunter at airshows. It was becoming ever so apparent that this novel idea had serious potential.
In 1961 not long after the P.1127 first flew, the Air Ministry put forth a requirement calling for the P.1127 to be upgraded to be low altitude tank busting strike aircraft with a maximum capability of 8G, but no less than 6G at 400 knots. This posed a serious challenge as the P.1127 had many high subsonic maneuvering flaws. Both the P.1127 and early wing design Kestrels, at speeds .88 Mach and above the wings would experience local stalling over substantial areas of the outer wing, leading to harsh wingrock and poor handling qualities.
The supercritical eventuality. With the transonic qualities of the P.1127 and Kestrel being abysmal at best it was time to reevaluate the entire wing layout. A supercritical airfoil, higher aspect ratio, and leading edge extensions all added to the goal of care free maneuvering at all airspeeds. Finally they had the shape they wanted with no serious handling issues to note except inefficiencies with the wing-tip vortices, this was later fixed on the Harrier with wing tips extending beyond the out-rigger landing gear. The last ounce of performance was squeezed from this small and light weight wing by the addition of 10 vortex generators for the mid and outer sections of the wing. These fences greatly improved the maximum Lift Coefficient at greater angles of attack compared to a bare wing.
The Kestrel FGA.1 was the final prototype variant of the first generation Harrier series, being placed in a Tripartite squadron between the UK,USA, and West Germany. The purpose of this squadron was to evaluate the real world effectiveness and usefulness of a VSTOL strike fighter. The results determined that this VSTOL idea, was very much a reality and NATOs only air power available in an all out war with the Warsaw Pact.
General combat performance and handling
The Kestrel will not be able to combat thrust vector as the nozzles were only designed to swivel up to a maximum speed of 250 knots IAS. The kestrel will be capable of attaining high AOA and maintaining good controllability up past 20 degrees AOA. Sustained G capability would be around 6G with the max G capability being 7G. Cornering speed would be between 400 and 450knots. Here you can expect up to 20 degrees per second in max instantaneous turn rate.
The kestrel was fitted with 2 pylons, 1 under each wing. On these pylons the kestrel only ever carried either 100 gallon fuel tanks or rocket pods operationally. However it is very likely that 30mm gun pods could have been mounted under the belly, and 1000 lbs bombs and fire bombs could have also been carried under the wing. This is due to the kestrel having a nearly identical fuselage to the harrier. However there was no need to further the armament capability of the kestrel as the first pre-production harriers were already being made. The cockpit was just equipped with a standard light fighter gunsight.
Specifications:
Spoiler
Powerplant - Bristol/Siddeley Pegasus 5 (15,200 lbs thrust)
Engine Temp limit 640 degrees for VTOL 595 for combat
Rate of climb (from wheels rolling) 12,000 feet per min (61 meters/second) 20,000 fpm (102 m/s) combat climb
Max VTO 13,750 lbs
Fuel capacity 632 gallons (5056 lbs with 8.0 pound gas)
Statcard:
Max speed 595 knots at sea level (684 mph - 1100 kph)
Max Altitude 47,000 feet (14,325 meters)
Turn time 27 seconds
Rate of climb 20,000 feet per min (102 m/s)
Takeoff run 0
Sources:
Spoiler
AV-P69-PN (Pilots notes Kestrel F.G.A Mk.1)
Operating Data Kestrel FGA Mk1 BS Pegasus 5 engine
Profile Publications (The Hawker P.1127 and Kestrel)
THE INFLUENCE OF V/STOL ON WING DESIGN AND TAILPLANE DESIGN (C.L.Bore Head of Research British Aerospace PLC: Kingston)
Aerodynamics of V/STOL aircraft (D.C Leyland)
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