jflaxman on DeviantArthttps://www.deviantart.com/jflaxman/art/Whirlwind-UAV-354873272jflaxman

Deviation Actions

jflaxman's avatar

Whirlwind UAV

By
Published:
10.8K Views

Description

Vertical takeoff and landing (VTOL) has obvious military applications as it eliminates the need for runways and allows aircraft to be based almost anywhere. It has been achieved with helicopters, though these machines suffer from short ranges and low top speeds; heliplanes, which offer better performance but are more mechanically complex; tiltwing or tiltrotor systems, which offer better performance again at the cost of much greater complexity; and vectored thrust systems, which offer the best performance of all, but share the disadvantages of tilt wing systems, burn more fuel and produce more heat and noise.

Tailsitter aircraft provide another solution that combines high performance with mechanical simplicity. These machines take off vertically nose first, lower the nose for forward flight, and raise the nose again to slow down and land vertically tail first. In spite of its advantages this system has rarely been used due to the difficulty of landing. A normally seated pilot’s backward vision and depth perception is severely reduced, and even the most skilful find landing in good conditions challenging; conditions rarely found in war zones. Safety is another issue, as engine failure while climbing or descending vertically will cause the aircraft to fall like a stone.

These problems are less serious for unmanned aerial vehicles (UAVs) which can land with the help of onboard sensors and/or be remotely controlled by operators on the ground. The Whirlwind takes the concept further with several innovative features not seen on any UAVs or tailsitters until now.

Design Features:

- The first UAVs were small powered gliders used for unarmed reconnaissance. They were cheap to operate, but as they were slow and needed runways they spent much of their flying time travelling to and from objectives. The Whirlwind burns more fuel and is louder on takeoff and landing, but can operate from any small patch of relatively level ground. It can also be deployed from flat-topped buildings or large vehicles. Ground crew can refuel and rearm it closer to a combat zone and move or hide more easily than normal airfield personnel.

- The Whirlwind’s canard configuration (small forward and large rear wings) combined with an upper and lower tailfin provide more stability on the ground – an important factor for a small aircraft that can be more easily knocked or blown over. Landing gear consists of five shock-absorbent legs that retract into pods during high-speed flight. Each leg is tipped with a castor wheel, allowing ground crew to easily push the Whirlwind under cover after use. The Whirlwind’s small size allows it to be hidden in larger buildings, tunnels, caves, etc; when not immediately needed it can be disassembled and stored in a smaller space.

- The Whirlwind’s rear mounted engine keeps the centre of gravity low during takeoff and landing, further aiding stability, while the main wings support its weight during flight. The engine drives two central rotors via a short camshaft. These rotors spin in opposite directions, generating neutral torque. The CPU and forward sensors are positioned ahead of the rotors, improving the Whirlwind’s ability to spot destinations or targets.

- Though slower than most jet aircraft, the Whirlwind is much faster than other VTOL systems that use comparable powerplants. The lack of a cockpit and life support systems permits a lighter, more efficient airframe. If the Whirlwind is remotely controlled, pilot fatigue is less of a problem as another operator can more easily take over. Operators do not have to be as fit as other combat pilots, making the Whirlwind ideally suited to those who want to go on serving despite age or injuries; and losses to crashes or enemy action pose less risk to its human crew.

- Unlike most older UAVs, the Whirlwind was always intended to be capable of combat roles. Various light missiles can be mounted on the wingtip pods which lie outside the rotor arc, and a 12.7mm machine gun in the nose provides a simple, cost-effective means of destroying the older, slower UAVs still commonly used for reconnaissance. Owing to the Whirlwind’s small size, firing any of these weapons will affect its handling, but this can be corrected through trim.

- The Whirlwind is only lightly armoured; most of its protection comes from its small size and agility. Its heat signature is very low, but the large rotor arc makes it easy to detect with radar. It is also vulnerable to electronic countermeasures, though these are rarely used by militia or insurgents, who more often try to shoot it down while it is taking off or landing.
Image size
1654x2338px 464.13 KB
© 2013 - 2024 jflaxman
Comments11
Join the community to add your comment. Already a deviant? Log In
Jimbowyrick1's avatar

Beyond Luft46!

- PAV