CharlieOneSix
6th Aug 2012, 09:28
Does anyone remember this NATS trial?
On the clear nights of 22nd, 23rd and 24th January 1980 I spent 5 hours 35 minutes flying a Bolkow 105 helicopter on NATS SSR trials at Heathrow. If I recall correctly this was carried out at about 7 locations within 10 miles of LHR. Each location had an Army searchlight team stationed there and a pencil beam of light was shone vertically upwards by them. My task was to hover at 500ft AGL alongside the beam and then slowly climb vertically upwards to 5000ft using the beam as a reference – a fairly difficult and daft bit of helicopter flying if I may say so! Hovering in free air at 5000ft by day is difficult enough, let alone at night.
All the time we had to shine a searchlight fitted in the cockpit at a point on the ground near LHR which in turn was shining one at us so we could see their reference point – presumably so the elevation angle of the ground based light gave our height above ground at any one time.
I remember it being rather difficult to keep station on the army’s searchlight beam and several times we ran out of tail rotor authority whilst hovering and climbing crosswind trying to keep our onboard light shining at the ground reference station and I had to dive away and start again. It was also damned cold with the doors open to facilitate our cabin based searchlight and my logbook recalls it was -13C at 5000ft.
I never did know in detail what we were trying to achieve and after 32 years it would be good to understand!
On the clear nights of 22nd, 23rd and 24th January 1980 I spent 5 hours 35 minutes flying a Bolkow 105 helicopter on NATS SSR trials at Heathrow. If I recall correctly this was carried out at about 7 locations within 10 miles of LHR. Each location had an Army searchlight team stationed there and a pencil beam of light was shone vertically upwards by them. My task was to hover at 500ft AGL alongside the beam and then slowly climb vertically upwards to 5000ft using the beam as a reference – a fairly difficult and daft bit of helicopter flying if I may say so! Hovering in free air at 5000ft by day is difficult enough, let alone at night.
All the time we had to shine a searchlight fitted in the cockpit at a point on the ground near LHR which in turn was shining one at us so we could see their reference point – presumably so the elevation angle of the ground based light gave our height above ground at any one time.
I remember it being rather difficult to keep station on the army’s searchlight beam and several times we ran out of tail rotor authority whilst hovering and climbing crosswind trying to keep our onboard light shining at the ground reference station and I had to dive away and start again. It was also damned cold with the doors open to facilitate our cabin based searchlight and my logbook recalls it was -13C at 5000ft.
I never did know in detail what we were trying to achieve and after 32 years it would be good to understand!