Here’s a first article of a series dedicated to trouble-shooting. In this one we’ll explain how the auto-hover is operated on our AW139 version 4.00.
What you need to get first is how the auto-hover works in this very first release. Basically it works as the real one, once activated it will reduce all your X and Z axis velocity vectors to zero knots, in other words it will decelerate your horizontal directions until the helicopter will stay in position without speeding up, unless you decide. The Y axis, or vertical direction and speed, will be controlled through the collective. The more you raise it the higher the ascending speed and vice versa. Yaw, or nose heading around Y axis, is controlled with the pedals. Once activated, the autopilot attempts to keep the your heading steady. In adverse weather conditions, you may be asked to act a little bit more on the pedals. As explained in the guide provided with the product, auto-hover shoudn’t be engaged above 20 KTS. This is the limit speed above which the helicopter will have to reduce too much speed to keep the helicopter nearby where desired. Engaging the auto-hover abobe 20 KTS may give unpredictable results.
TYPES OF AUTO-HOVER
We’ve been actually implementing two types of auto-hover.
- Type A is hands-ON-controls is untied to the FT (force trim) system of the aircraft, in order to leave the pilot more control on the rolling and pitching axis. It’s designed to help out during manouvers, approaches, in adverse weather conditions and can be used to decelerate the aircraft.
- Type B is hands-OFF-controls and is tied to the FT (force trim) system. This is the stablest hovering mode and lets you put your hands off flight controls. When type B is engaged the nose pitches up +10° as described in this article. Being in conjunction with flight trim means that you can trim the direction and speed of auto-hover. As the real one, never exceed 60 KTS in this mode.
The two modes are mutually exclusive. They can be switched by switching ON (type B) or OFF (type A) the FT (force trim) switch on the MISC panel and then pressing HOV (hovering) mode button below on the FD (flight director) panel.
When Type B is engaged and no joystick is present, the collective raises automatically to the right blades pitch value, in other words it lets you achieve an automatic take-off, putting your aircraft steady ±5 ft.
CHANGES ON THE MFD
HOV mode is designed to reduce horizontal speeds to zero, as in reality. This means you will always control the ascent or descent of the helicopter through the collective. When activated, the HOV mode changes the HSI on the MFD with a compass showing the velocity trend and direction, just like the real one.