Background to the Flight
The accident flight was a return trip from a private site near Hawarden to a private site near Romiley. The passenger had flown the helicopter to Hawarden and was then taken back as a passenger. The pilot, who held a Private Pilot’s Licence with 355 hours total flying experience (354 on type), had not previously operated a helicopter into the Romiley site but had been there as a passenger. The helicopter was not fitted with dual controls during the flights.
History of the Flight
The weather was good, and the surface wind was reported as 030° at 17 kt by Manchester Air Traffic Control during the return transit. There was no windsock at the Romiley landing site. The helicopter appeared fully serviceable.
During the approach, the pilot established a descent on a north-westerly direction over power lines and trees east of the landing site, then turned left onto a southerly heading. He reduced airspeed until the helicopter was in a high hover at approximately 75 ft above ground level just east of the site. To maintain the hover, the pilot used almost maximum permitted manifold pressure. He then began a slow right turn to align the helicopter into wind for landing. The turn was initially stable, but the pilot then noticed the helicopter descending. Aware that a vortex ring condition was possible and that the surrounding area limited fly-away options, he lowered the collective lever with the intention of raising it to cushion the landing. Close to the ground, he raised the collective, but the right skid contacted the top of a wooden fence, and the helicopter toppled onto its right side. The pilot turned off the fuel before exiting with his passenger through the left door.
Relevant Information
The Robinson R22 Pilot’s Operating Handbook includes the following relevant points:
- Hover controllability is substantiated in 17 kt wind from any direction up to 9,800 feet density altitude.
- At 75 ft agl, the helicopter should be at a minimum airspeed of 52 kt to remain clear of the Height-Velocity diagram’s avoid area.
- Never make takeoffs or landings downwind, especially at high altitude, because the loss of translational lift can cause the aircraft to settle into ground obstacles.
- A vertical descent or steep approach downwind can result in settling with power (vortex ring condition), where the rotor settles in its own downwash and additional power will not stop the descent. Recovery requires reducing collective and lowering the nose to increase airspeed, which can be dangerous near the ground.
LASORS Safety Sense 17 provides advice on operating into private helicopter sites and refers to information on the British Helicopter Advisory Board website. It states that conditions likely to result in vortex ring include power on, low indicated airspeed (below 35 kt), and a high rate of descent (over 300 ft per minute).
Pilot’s Comments
The pilot assessed that the helicopter likely entered a vortex ring situation and that the proximity of the fence meant he had no chance of achieving a clear landing. Reflecting on the unusual wind direction and its strength, the pilot considered that it would have been appropriate to carry out at least one overflight of the site to assess the situation and the preferred approach path before attempting a landing. He also acknowledged that, given his lack of flying currency (0.8 hours in the last 90 days), he should have undertaken continuation training before landing at the site.
Damage and Injuries
The helicopter sustained substantial damage. The pilot received minor injuries; the passenger was uninjured.