SAS, I can only imagine the “fun “ doing heads down night position keeping on a FLIR display at what sounds like significant altitude. I’m assuming the flight vehicle was absent any control augmentation to assist? Varying winds etc. Sounds a very very ultra high concentration task.
John,
A BK-117 with no SAS......known amongst the EMS crowd as the original "Vomit Comet" due to the things instability.
We tried doing it with just the Mark I eyeball of the Co-Pilot trying to look down but the Test Folks nixed that for lack of accuracy.
So after a Coffee and some brain storming....I suggested using the FLIR and we tried that and our success improved but still not good enough.......then we realized we had to compensate for the hover attitude of the aircraft and slew the FLIR to an appropriate setting aft of FLIR vertical to achieve "Aircraft" vertical and it worked way better.
It was very hard work....looking out on NVG's....listening to the CoPilot's steering commands....sneaking a quick look under the NVG's to the FLIR screen to see where the cross hairs were pointing....remembering they slid around depending upon the movement of the helicopter both in a horizontal plane but in all the other axis as well due to the control inputs and turbulence of the Out of Ground Effect Hover and wind speed variations.
It was a large smoke stack.....but it would have gone a lot better and easier had it been the size of a Cooling Tower not so far away!
The hole got very small when looking at it from three thousand feet.