| Picture |
|
| Manufacturer |
McDonnell Douglas
|
| Type |
MD520N
|
| Introduced |
1/1/1991
|
| In production? |
Yes
|
| Units produced |
0
|
| Price US $ |
1,900,000.00
|
| Overall Length |
32.1 ft
|
| Length |
25.5 ft
|
| Height |
9.8 ft
|
| Width |
4.6 ft
|
| |
|
| |
|
| Description |
The MD520N is a lightweight, five-seater turbine powered helicopter based on the MD500 design. It uses a five-bladed, fully articulated rotorhead. Unusual is the use of NOTAR (NO TAil Rotor) as the anti-torque system, which claims a higher degree of safety due to the absence of a tail rotor.
The NOTAR system makes use of the rotor downwash, which is deflected over the tail boom by two Coanda slots that are fed with low pressure air generated by an engine-driven fan at the root of the tail. In this way, the rotor downwash is deflected, generating a lateral force (much similar to a wing), which counteracts engine torque by 60%. The other 40% is created by venting air through variable aperture louvres at the end of the tail boom. This mechanism is also used for yaw control.
Another advantage of the NOTAR system is that it produces less sound than a conventional tail rotor, making it one of the quietest helicopters around.
|
| Advertisement |
|
| Design features |
- NOTAR (NO TAil Rotor) system based on fan blowing air through Coanda slots in the tailboom
- Jaw control by a controllable thruster at the end of the tailboom
- Graphite composites tailboom
|
The MD520N is a lightweight, five-seater turbine powered helicopter based on the MD500 design. It uses a five-bladed, fully articulated rotorhead. Unusual is the use of NOTAR (NO TAil Rotor) as the anti-torque system, which claims a higher degree of safety due to the absence of a tail rotor.
The NOTAR system makes use of the rotor downwash, which is deflected over the tail boom by two Coanda slots that are fed with low pressure air generated by an engine-driven fan at the root of the tail. In this way, the rotor downwash is deflected, generating a lateral force (much similar to a wing), which counteracts engine torque by 60%. The other 40% is created by venting air through variable aperture louvres at the end of the tail boom. This mechanism is also used for yaw control.
Another advantage of the NOTAR system is that it produces less sound than a conventional tail rotor, making it one of the quietest helicopters around.
|
|
- Advertisement -
|
Design features:
- NOTAR (NO TAil Rotor) system based on fan blowing air through Coanda slots in the tailboom
- Jaw control by a controllable thruster at the end of the tailboom
- Graphite composites tailboom
|
| Persons |
5
|
| Max. Range |
0 mi
|
| Cruise Speed |
142 mph
|
| Max. Speed |
175 mph
|
| Max. rate of Climb |
1775 ft/min
|
| HOGE ceiling |
6000 ft
|
| Service Ceiling |
20000 ft
|
| Gross Weight |
3350 lb
|
| Empty Weigt |
1585 lb
|
| Useful Load |
1764 lb
|
| Fuel Capacity |
64 gallons
|
| Number of Engines |
1
|
| Engine Type |
Turbine
|
| Engine Code |
Allison 250-C20RS
|
| Horse Power |
450
|
| Rotorhead |
Fully articulated
|
| Number of rotorblades |
5
|
| Rotor Diameter |
27.4 ft
|
| Number of tail rotorblades |
0
|
| Tailrotor Diameter |
0 ft
|
|