Autorotation question

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seneca2e
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Joined: Mon Feb 11, 2008 10:35 pm

Autorotation question

Post by seneca2e »

When you do an auto in the Brantly do you tend to come in with some collective during the flare or do you keep it all in reserve until after you have leveled the ship with the cyclic? Dennis Kenyon of Enstrom fame actually used to own a B2B and the quote below is from him. This is different from the Brantly-Hynes manual(used during the heavy training period of the 70's) which has you bringing in collective only after you level off after the flare with forward cyclic. Initial approach speed is higher at about 65-70 mph presumably to allow a more aggressive flare. I notice that it sure seems like I can't get the descent to a comfortable level with just the flare alone without a little "collective check" but so far I've just done power recoverys. If it was all the way to the ground not sure if it would work out doing it that way(using up some collective reserve in the latter stages of the flare means you're not going to have it to cushion the subsequent post flare descent). So what do you think? How do YOU do it?

"Brantley Autorotation Handling.

Just a few notes that may help, gained from my 1970s experience of the G-AWDU B2B I once owned at Shoreham.

As mentioned before .... a nice ship which I was happy to own and just to say the CSE accident that took that lovely guy, Graham Meyrick from us was a 'one-off' (I cannot find any later instances of a similar blade separation) Incidentally at the time Graham was teaching Cy Rose's son to fly and I wonder if any PPs out there have any news of Cy. He was co-founder of the HCGB along with Tony Everard circa late 1960s I believe. Cy's son Greg was a highly talented sculptor in ceramics ... any news of him these days ?

But to get back to the original post and question. I quite liked the autorotational handling of the B2 which in my view was better than the 269 series and not far off the Enstrom in docility.

I used a standard 'steady state' auto speed of 45 to 50 knots in the descent bringing the initial cyclic flare in at 30 to 40 feet depending on weight and w/v. In the latter stages of flare, approx one third to one half of available collective is introduced as cyclic flare is tightened so for a second or two, both controls are being worked. Forward speed seems to bleed off quite quickly in the sink and with a slight breeze and firm cyclic, it is possible to reduce ground speed to almost zero.

With the T/R position at say ten feet AG, firm forward cyclic is necessary to achieve the skids level attitude for landing and as the machine continues sinking for the final touch down, further collective lever is used IN ARREARS to ensure a soft touch down with zero or minimum forward speed.

Generally, some right pedal is required to maintain direction as T/R authority decreases and of course .... no further lowering of lever following initial skid contact in the run-on.

Using the above sequence and favourable a/c weight and W/V , the B2 can be put down to a full stop landing with RRPM remaining in the green, albeit my experience was that at MGW, adverse density and low wind speed some residual run-on landing speed has to be accepted.

I'd have to say, being one of the more mature rotary guys, I imagine any youngsters flying the type may well have developed better techniques, but the above handling WILL ensure a non damaging landing in a real 'engine stop' given some helpful circumstances and previous type practice.

I don't know of any B2 training in the UK at present, but there must surely be a couple of 'old lags' out there who once used the type for training in the UK.

But in the 'don't try this at home' department, I have to say this exercise MUST be briefed by and practiced with a competent and type experienced instructor.

In closing .... can any ppruner tell us the latest factory position on production, and the posted selling price. I can't help feeling that IF there is some solid factory support with stocked parts, surely someone will get the type back in a UK training school.

Oh and it was a B2 that was flown into the 007 crater. I think the pilot was Pete Peckowski. Anyone know differently ?

Take care lads,

Dennis Kenyon."
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Ron Spiker
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Re: Autorotation question

Post by Ron Spiker »

I've started several times to reply to your post and deleted it each time. The short answer is "it depends", on the airspeed, rate of descent, rotor rpm, target, etc. Come see me or another Brantly instructor of your choice for emergency procedures practice. I can run you through about every type of auto we can think up, but I won't recommend or suggest emergency procedures techniques online. Sorry. Perhaps someone else will. I'd be glad to work with you on them in the helicopter though.
seneca2e
Posts: 395
Joined: Mon Feb 11, 2008 10:35 pm

Re: Autorotation question

Post by seneca2e »

Dennis is one of the best helicopter pilots alive and his response on a similar thread was amazingly detailed as you can see. Brantly-Hynes trained a lot of pilots in the 70's using a different technique-one more closely aligned with how I did them in the Enstrom to the ground power off. With a power recovery in the Brantly coming in with the collective early makes for a relatively sedate outcome. If anyone has done them all the way to the ground power off just wondering which technique they used. In the R22 it's pretty much flare, level, then collective to cushion.
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