"There are two types: flare and turn, and turn and flare. Heights and speeds will vary according to type. For a flare and turn, I would be flying downwind at 90kts and 50'. Initiate with flare, maintaing height and direction, and then start the turn into wind to end up pointing into wind with about 30-40kts still at 50'. Come to the hover, then forward and down."
One word of warning, this is what most people might think that they are doing and come unstuck.
They start to flare, I.E. decrease airspeed, then sink, (as they wish to descend to the target) then pedal turn instead of cyclic turn, then they’re right where old mates DMNH and AOTW describes.
The only safe way to do it is turn with cyclic (steep co-ordinated turn) first half of the turn, and then second half of the turn as you are coming into wind commence the quick stop. Note how little power is reqd.
Now do it the other way that DtP first asked about (if you are stupid enough), note the power required, safety margins, and where oh where is that safe EOL picture?
AOTW describes the downwind VRS situation well and I suggest that there is no clear cut definition as Nick has isolated. That entry and many variants of it are just as good to get you sailing downawards and light on the seat. Why not look at a recent video of a seaking crash onto the back of a frigate or destroyer or some such. Note that he is sailing along in almost the same vortices configuration thanks to the ships superstructures, as AOTW describes, note the M/R coning flex abruptly two or three times as it unloads in incipient VRS.
As an analogy to the possible combinations reqd for LL VRS one might refer to a recent media report where some of the world best mathematicians finally gave up on trying to formulise the surf, breaking-wave actions.
I think that would be very simple compared to our rotor blades actions and reactions, not to mention the unseen winds vortices and currents afore you even got there.
At the end of the day when close to the ground, Downwind, Descending and Decreasing A/S, in the same handful is the same as Drinking, Driving and Destruction.
WW. No the disc has no idea which way it goes and it is also totally irrelevant as to which way the aircraft is pointing, the only relevance is the actual movement of the disc relative to the surrounding air and whether you might also be encountering or projecting vortices in front of it to then fly into.
There was a super good article in the Rotor and Wing Mag. (The Subtle Hazards of Light Winds) sometime in 1984, I use it as a bible and the numbers are nowhere near Nick’s, mind you it referred to light helicopters.
Nigelh, I agree at times esp. in the R22 in can be difficult to simulate and the running oneself out of puff and then overpitching, which is another story, is something that will get everyone sooner or later if they live close to the ground.
tet
Last edited by topendtorque; 4th Feb 2007 at 12:22.