Helicopters have autopilot, though it isn’t as commonly found in helicopters as it is in airplanes. This is because helicopters are unstable aircraft, especially when compared to planes.
So while advanced autopilot systems do exist on helicopters, it is challenging for them to fully control flight and means that any autopilot system installed is typically very complex and therefore costs a lot to design and manufacture, thereby pushing up the price of a helicopter.
How Does Autopilot in Helicopters Work?
Fundamentally, autopilot must be able to detect any changes in helicopter altitude and then respond to these changes just as or even more efficiently and smoothly than the human pilot can.
Therefore, in plain English and without getting technical, an autopilot system must know the pilot’s desired attitude, the actual altitude, compare the two, and then correct for the difference and control the speed of the correction.
What Does Autopilot in Helicopters Control?
You probably know that helicopters are very complex aircraft and pose a challenge to fly. This is because they are dynamically unstable, especially in pitch and roll in hover.
It’s therefore important to know that the extent of what the autopilot system can control in a helicopter can vary. This can range from basic flight stabilization and holding a set altitude with approach guidance to the complex task of hovering, which is undoubtedly the hardest part of flying a helicopter.
What is Autopilot Used For?
At its essence, autopilot is used to take care of the routine repetitive tasks, which then allows pilots to focus on other concerns during flight.
Autopilot systems in helicopters are therefore generally used for the following purposes:
- Long-distance flights
- To allow pilots to alter navigation
- When flying under IFR or at night
- For better time and fuel management
- To maintain accurate positioning in busy airspace
Can Helicopters Hover on Autopilot?
Yes, helicopters can hover on autopilot, though this can certainly be a challenge to design and engineer, especially faultlessly.
This is because compared to fixed-wing aircraft such as airplanes that are controlled in pitch, roll, and yaw, helicopters are controlled through cyclic (roll and pitch), collective, and throttle, with the anti-torque pedals as well to control yaw.
This means that the cyclic must be controlled over its target with no lateral movement, in addition to collective and throttle to maintain constant altitude.
As mentioned, the extent of what an autopilot system can control varies. An auto hover system is by far the exception rather than the rule and does not apply to the majority of helicopters, especially lower-end helicopters, due to a combination of the lack of necessity, price and therefore a lack of complexity.
Helicopters with auto hover capability include the following:
- Bell 412
- Bell 525
- Sikorsky S-76
- Sikorsky S-70
- Sikorsky S-92
- AgustaWestland AW101
- AgustaWestland AW139
- AgustaWestland AW189
- Eurocopter EC225
- Eurocopter EC725
- NHIndustries NH90
What Was the First Helicopter With Autopilot?
The Piasecki HUP-2 Retriever, which was introduced in February 1949, was the first production helicopter with an autopilot; it could hover at 15 meters. It was primarily used by the United States Navy, United States Army, Royal Canadian Navy, and French Navy.