Viscount question

[Nigel H-J]

OK, it may be in the manual but presently at work so hoping some-one can tell me - when flying the Viscount I keep the climb and descent to 1,000fpm - what was the correct climb and descent figures for this aircraft? I know a lot will depend on weight but the average figure would be appreciated.

Many thanks in advance

Nigel

[TSR2]

I'm pretty sure that the climb is 1000fpm MAX.

[Nigel H-J]

Hi Ben

Thanks for that, when taking off even when fuel is only at 20% all tanks the speed on climb out at 14,000rpm at 1,000fpm slowly builds up and until at safe height I reduce the power further to maintain around 160kts @ 1,000fpm.

Kind regards
Nigel

[TSR2]

I'll need to try it again Nigel, On my test flights from Stockholm I'm pretty sure I had to drop down to 600 - 700fpm to keep a decent airspeed (although she was pretty heavy) Remember airspeed is always king as that's what keeps you in the air.

[Nigel H-J]

Thanks Ben, will look forward to your reply, usually I tend to keep the a/c low on fuel and around 60 - 75% auw of the maximum. Descent would be kept to 1,000fpm then also?

Kind regards
Nigel

[TSR2]

Hi Nigel,

When you say "low on fuel" how low? Can you give us an example of a rout and then how much fuel you would typically use for that route?

[Nigel H-J]

Hi Ben, off the top of my head flying from Heathrow to Birmingham and return I usually have around 2,600kg of fuel on board but cannot for the life of me remember how much remaining after landing back at Heathrow though it is low. If I have time tomorrow will do a flight and let you know

Nigel

[TSR2]

I'm doing some upgrade work on the PC tonight, so it will be tomorrow by the time I do a test flight, hopefully our Fraser will have popped by in the mean time with a more factual response! lol

[Nigel H-J]

Thanks Ben, I will do another Brum and return flight to Heathrow tomorrow loading up with 2,600kg of fuel from empty and let you know tomorrow night.

Kind regards
Nigel

[Viscount Cornbank]

Hi Nigel

As Ben mentioned, the rate of climb is incidental. You fly the airspeed. On all types once cleaned up after takeoff and climb/cruise power is set, accellerate to 180kt and maintain that speed. On all but the Viscount 810, which is more powerful, this will yield an initial climb rate dependent on weight and temperature of 1000-1200 fpm. As the climb rate deteriorates, still maintain 180 kt until the rate reaches 500 fpm, probably around FL160-180, at which point reduce airspeed to maintain 500 fpm, but not below 160kt.

As far as the descent goes, reduce power to a minimum of 60-80 psi with fuel trim at zero, the rpm is incidental but should be around 10500-11000 rpm. Descend at a speed not greater than the current Vno, generally a descent rate of 1500fpm is more than adequate to descend from around FL150 to 2000 ft QFE in 45-50 miles at an appropriate speed.

You are free to carry whatever fuel you like, but VA operations require a 4400lb/2000kg contingency. The trip calculator on the back of the speed card will work it out for you

cheers

Fraser