Helicopter Vortex wake.???
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Fuji Abound
It could, but the incident in your link is not an example of it.
Extract from the AAIB report:
Something a bit larger is enough to kill you, sadly.
Extract from the AAIB report:
Conclusion
The outflow of air from the Sea King's downwash possibly affected the Cessna, when it became airborne and crossed vehicle access 'M'. The turbulence created by the downwash could have added to the Cessna pilot's control difficulties. It is also possible that the low speed and increasing high angle of attack of the Cessna as it rotated into the air may have caused the aircraft to stall and descend quickly after becoming airborne.
It was concluded that the Cessna crashed following a loss of control during an attempt to carry out a 'go-around'. The activity of the Sea King and the loss of control by the pilot of the Cessna were two distinct, and for the most part, unrelated events occurring at the same time. The plot constructed of the relative positions of each aircraft considered in conjunction with the rotor downwash trial established conclusively that the rotor downwash from the Sea King did not play any part in the Cessna leaving the side of the runway.
The possibility that the pilot of the Cessna was distracted by the actions of the Sea King could not be discounted. If that was the case, the option to stop on the runway by closing the throttle and applying the wheel brakes was available. The higher than normal speed maintained by the Cessna after landing was more likely an attempt to expedite clearing the runway than trying to take avoiding action. It is possible that expeditious runway clearance was either not to delay the departure of the Sea King or to reduce the time taken to travel to park at the Civil Air Terminal at the far end of the runway. The loss of directional control on the runway was attributed to the high ground speed and the attempt to carry out a 'go-around'. The go around was probably attempted to resolve the difficulties, experienced by the Cessna pilot, in maintaining directional control.
The outflow of air from the Sea King's downwash possibly affected the Cessna, when it became airborne and crossed vehicle access 'M'. The turbulence created by the downwash could have added to the Cessna pilot's control difficulties. It is also possible that the low speed and increasing high angle of attack of the Cessna as it rotated into the air may have caused the aircraft to stall and descend quickly after becoming airborne.
NB: The last para refers to what happened after the Cessna had gone off the side of the runway (on the same side as the Sea King was hovering), taking out a runway light as it did so and was bouncing over the grass.
Join Date: May 2006
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Helicopter Vortex wake.???
Large fixed wing or rotor, the effects can be deadly. Have a look at the following test. It makes you realise the unseen evil that lurks awaiting the unsuspecting pilot. A PA28 with a friend of mine ended up inverted at Humberside a couple of weeks ago due to the wake vortex from a departing helicopter leaving on runway 20 and he was landing into wind on 27. The westerly breeze blew the vortex towards the threshold just as the piper was approaching to land.
YouTube - NASA Airliner Wing Vortice Tests
YouTube - NASA Airliner Wing Vortice Tests
Avoid imitations
Join Date: Nov 2000
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I think everyone who isn't used to helicopters tends to underestimate their downwash, full stop.
Quite recently I watched a pilot park a PA-28 directly adjacent to us, already parked on the helipad, in a 3 tonne helicopter, ignoring the other parking spots further away in the same row. The pilot was about to walk away, also ignoring the tie-downs nearby and her aircraft control locks. The only reason I can imagine she parked there was that it was the closest parking spot to the clubhouse.
She seemed quite disgruntled when I walked over and politely advised her that it might be a good idea to at least put some tie downs on her aircraft's near wing, as we couldn't ground taxi and we were about to lift.
Quite recently I watched a pilot park a PA-28 directly adjacent to us, already parked on the helipad, in a 3 tonne helicopter, ignoring the other parking spots further away in the same row. The pilot was about to walk away, also ignoring the tie-downs nearby and her aircraft control locks. The only reason I can imagine she parked there was that it was the closest parking spot to the clubhouse.
She seemed quite disgruntled when I walked over and politely advised her that it might be a good idea to at least put some tie downs on her aircraft's near wing, as we couldn't ground taxi and we were about to lift.
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Here is a better example of the dangers. I was closely involved with the initial investigation of this sad accident and, even with considerable experience of operating military fixed wing in an intense rotary environment, I was as surprised as everyone else at the effect of rotor downwash in this case.
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Whilst looking for something pretty unrelated I came upon a report for the case which resulted from the incident reported above in the AAIB report at St Mawgans.
In essence the MOD lost the case and paid the relatives some £5M.
The quote is very simple and raises a variety of issues regarding how courts treat 'expert' reports
"Paton v MOD, £5 million settlement achieved the day before a 3 week Category A trial for a fatal claim arising out of an air accident, overcoming accident investigation reports by both the AAIB and the MOD which found the deceased to have caused the accident. Thought to be the highest award for a single fatality; "
In essence the MOD lost the case and paid the relatives some £5M.
The quote is very simple and raises a variety of issues regarding how courts treat 'expert' reports
"Paton v MOD, £5 million settlement achieved the day before a 3 week Category A trial for a fatal claim arising out of an air accident, overcoming accident investigation reports by both the AAIB and the MOD which found the deceased to have caused the accident. Thought to be the highest award for a single fatality; "
