A Convivial Aviation Discussion Forum for Aviators, Aviatrices and for those who think Flying Machines are Magic.
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If not tomorrow, what day would you prefer?TheGreenGoblin wrote: ↑Fri Oct 15, 2021 6:51 pmLooks looks like a successful autorotation and, run on (skid marks) but pity about the tail rotor. I wonder if the main rotor did that, did it hit the beach, or was it the cause of the in-flight emergency? Everybody walked away. Let the insurance people wrangle over it.
No helicopter emergencies for me tomorrow please.
PHXPhlyer wrote: ↑Fri Oct 15, 2021 8:08 pmIf not tomorrow, what day would you prefer?TheGreenGoblin wrote: ↑Fri Oct 15, 2021 6:51 pmLooks looks like a successful autorotation and, run on (skid marks) but pity about the tail rotor. I wonder if the main rotor did that, did it hit the beach, or was it the cause of the in-flight emergency? Everybody walked away. Let the insurance people wrangle over it.
No helicopter emergencies for me tomorrow please.
PP
1DC, the Goblin did indeed have a very satisfactory flight, in CAVOK conditions, while practising autorotations and vortex ring recoveries in near Rye. Handling was good, the subsequent approach and landing good, my hovering was good, my spot turns weregood! Headcorn and that area escaped the clag and rain further down the coast and the band of weather that crept down the M25 corridor further north later in the morning. Bumped into an ex Rhodesian army helicopter pilot after the flight, a little older than me, he is renewing his helicopter PPL but I was unable to tarry too long talking, as in my rush to leave in the morning I had grabbed the wrong keys from the household key rack, namely the key needed by my better half to open our neighbour's house, while they are on holiday, to feed their cats. Suffice it to say she was not impressed, and I was called every name under the sun, including incompetent, so I came back to earth with the proverbial bump as it were! What the cats thought of my idiocy is not recorded! Semper in excretum sum as they say!
The latest thoughts are that VRS is not what people think it is.....
I would be interested in your insight(s) into VRS/settling with power, G~Man. It is one thing practising with sufficient altitude to easily recover, another thing altogether if one is silly enough to get into this state near terra firma.
He is not very fluent, but the material is OK...
1964 - theory of helicopter flight lectures at 705 Squadron Culdrose for us pre-wings studes. Just finished one lecture and a different instructor takes the next lesson. He asks what we learned in the previous one, let's say it was about vortex ring. We told him and he says "No, no, I don't agree with that, what I think is.....". No wonder that 57 years later the alternative theories on the black magic of helicopter aerodynamics still abound!
You made my point---that is not a normal regime in helicopter flying. I suspect you have been taught to go to a hover @ 2k and start a vertical descent to in excess of 300 fpm then pull collective and recover.... Nobody does that.....the ONLY time I have ever done that is demonstrating VRS.... So why do flight schools keep teaching it....CharlieOneSix wrote: ↑Mon Oct 18, 2021 10:41 pmI went up in the brick built shithouse of a Wasp once with an ETPS graduate and he did a fully developed vortex ring demonstration. Scary! 9000ft start, recovered at 4000ft in what seemed like a few seconds.
Your question is good one. I guess recovery is taught that way because that is what will be examined in the flight test. Clearly this area needs to be rethought, retaught and tested in a different way by the CAA/FAA.G~Man wrote: ↑Tue Oct 19, 2021 5:04 amYou made my point---that is not a normal regime in helicopter flying. I suspect you have been taught to go to a hover @ 2k and start a vertical descent to in excess of 300 fpm then pull collective and recover.... Nobody does that.....the ONLY time I have ever done that is demonstrating VRS.... So why do flight schools keep teaching it....
Better way to teach is: "Do NOT fly into your downwash while descending". Take a look at these, none are VRS in the traditional sense yet all ended in tears...:
https://aviation-safety.net/wikibase/134286Prior to accepting delivery of the new helicopter, the pilot noticed a 4 percent decay in rotor rpm when the collective control was lowered after landing, activating the aural and visual LOW ROTOR RPM warnings. After a few seconds, engine and rotor speed returned to normal. The engine manufacturer said it should be of no concern as long as it operated normally during flight, but suggested adjusting the linear variable differential transducer after they ferried the helicopter home. On the day of the accident, the pilot intended to make a low pass and land at a hospital helipad. He lowered the collective control and noticed rotor rpm had decreased to 96 percent. The LOW ROTOR RPM warnings activated. He realized he was too low to attempt an autorotation. He reduced collective and pitch attitude further. RPM drooped to 90 percent, and stabilized. Approximately 20 to 30 feet above the helipad, the pilot raised the collective control to flare for landing. RPM rapidly deteriorated. The aircraft impacted the helipad in a tail-down position, rolled over, and came to rest on its left side. The operator found the rotary variable differential transformer rigged at 57.9 degrees of twist grip travel at the Flight Gate position. According to the A119 maintenance manual, the device is supposed to be rigged to achieve 60 degree ( or - 1 degree). The operator said misrigging of the rotary variable differential transducer would cause incorrect fuel scheduling to the fuel control unit.
Probable Cause: improper rigging of the rotary variable differential transformer by the manufacturer, resulting in incorrect fuel scheduling to the fuel control unit.