UK AAIB May 2010

[VeeAny]

A109 E G-TYCN
18 Jan 2010
Nr Blandford Forum, Dorset

Air Accidents Investigation: Agusta A109E, G-TYCN (http://www.aaib.gov.uk/publications/bulletins/may_2010/agusta_a109e__g_tycn.cfm)

Report name:
Agusta A109E, G-TYCN

Registration: G-TYCN
Type: Agusta A109E
Location: Private field, Blandford Forum, Dorset
Date of occurrence: 18 January 2010
Category: Public transport - Helicopters
Summary:
At approximately 100 ft agl during an approach to land, the pilot noticed an increased rate of descent, which he tried to arrest by raising the collective control and the aircraft nose. This had little effect and the aircraft landed heavily despite the application of maximum torque just before touchdown. The aircraft bounced into the air and swung through approximately 250° before coming to rest. It is likely that the aircraft entered a votex ring state from which it was unable to recover in the height available.

[212man]

Good old Vortex Ring - if in doubt, blame it on VRS!

[VeeAny]

212Man

My thoughts exactly, which is why my omission of the description was deliberate and not accidental for once !

The Narrative in my post was added by someone else not me !

Whilst not in a position to judge and not commenting on this one specifically I tend to treat most reported VRS accidents with a pinch of salt until proven otherwise.

Gary

[Two's in]

He thought that flying a normal approach at high aircraft mass and low airspeed with a slight tail wind had led to the high rate of descent which he had been unable to arrest.

This is always better as a pre-flight briefing point than a post-accident statement.

[VeeAny]

I have been asked about my comments above off Forum.

To be clear I am not pointing a finger at the pilot in this case at all, I am making a point that VRS gets blamed for lots of things, quite often questionable performance issues coupled with a high ROD are not necessarily VRS. Sometimes it gets blamed because the pilots cant come up with anything better. Having read a lot of accident reports , a fair proportion of them which are based upon 'Form submitted by pilot' cite the cause as VRS.

This guy may have had all the ingredients for it, he may have not I wasn't there I just don't jump on the bandwagon too easily, particularly having spoken to pilots who have observed accidents which are subsequently blamed on VRS when in fact the root cause was poor technique or operating overweight (once again not commenting on this case).

Completely Off Thread Now.
I am planning to put this in as a subject in the safety evenings with some pretty strong supporting evidence, I know there are instructors out there who are scared of it and hate demoing incipient stage recovery. A bit more understanding can do none of us any harm. I might even be able to persuade a test pilot or two to throw their comments in to the mix.

[Senior Pilot]

I added the quote from the AAIB Report, to make it easier for Rotorheads to follow the thread without having to go off onto another tab to read the link. It is simply a quote from the AAIB linked in the OP and is not in any way a comment, nor is it editorialising.

[VeeAny]

Splot

With hindsight its what I should have done in the first place.

Gary

[Shawn Coyle]

Veeany
Demonstrating incipient VRS is no more dangerous than demonstrating stalling in a FW airplane. PM me if you want specifics of how to demo.
And VRS can happen any time the downwash velocity equals the velocity of the airflow coming up into the rotor. A badly carried out approach with a large flare and a pull on the collective at the wrong time can do it.
My view is that VRS often doesn't get blamed when it should.
I looked at a Lynx accident many years ago that had VRS written in bold letters all over it and yet the Army Board of Inquiry didn't even consider it.