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Old 10th Apr 2022, 13:21
  #120 (permalink)  
albatross
 
Join Date: Sep 2004
Location: Canada
Posts: 1,746
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I will probably get a lot of flak for this but:
I was doing a job which entailed a lot of climbing, descending and hovering at high altitudes AGL.
I discovered that it is possible to enter VRS from a steady hover.
It was a great surprise the first time.
Due to the job it happened a lot. So I got the chance to try various things out.
Maintaining a vertical descent pulling power just increased the rate of descent.
Controls got sloppy but the aircraft did not enter any unusual attitudes.
There were no torque or RPM fluctuations.
Recovery was simple, Initiate forward or sideways movement and exit the column of descending air.
The aircraft was very light during these operations just myself and sometimes 1 passenger and around half fuel.
It warned you it was going to enter VRS. You would be happily sitting there at about 80%Q. The VSI would flicker (not even to 100FPM down) Altimeter would hardly move. If you did nothing it would enter VRS shortly thereafter. Pull a bit of collective and it usually entered VRS immediately and fully.
It only happened in calm wind conditions.
As we were hovering, climbing or descending on a ‘Laser’ beam you were never moving more than 2 feet in the horizontal from ground level to as much as 7000 AGL. Usually we only climbed 2000-4000 ft.
If you lost the ‘Laser’ beam you had to descend to ground level in order to reacquire it so sometimes I remained in VRS to descend.
The aircraft was being observed using a 50x theodolite so the surveyors could see the aircraft depart downwards. They would have me in the crosshairs as I hovered and suddenly I would depart downwards. They thought it was very funny to watch.
Just for info the aircraft had a cowling just abut under the fwd seats. The cowling had a screen on the bottom. Inside the cowilng was a video camera focused on the screen and a small 3 inch square monitor was installed on the instrument panel. A 10 amp gyro stabilized ‘Laser’ was placed on the ground pointed vertically upwards. You hovered low over the ‘Laser’ and placed the aircraft over it until you saw the ‘laser’ dot on the screen. You then initiated a climb at about 6-800 FPM keeping the dot as close to the center of the screen as possible. If you rapid control movements failed in this and you lost the dot you had to return to ground level and start over again. It took a lot of practice to learn the technique usually about 5 -10 hours. Some guys caught on quickly, some never could. The customer paid fro the training. They also allowed you to go out and practice if you didn’t do a shot for a day or two as it was a skill that required constant practice. Totally an eye, hands, feet coordination thing…if you had to think about it the dot was gone.

Last edited by albatross; 10th Apr 2022 at 13:56.
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