Aircraft reluctant to take off

Are the brakes still on?

lol sorry could not resist. Not really familiar with each plane... so I am not very constructive here.

So far as I know the brakes are fully off as acceleration up to what should be takeoff speed seems reasonable for the type of aircraft.

Lighten the payload and the fuel and see if that works, it should.

If they are freeware, post a link and I'll take a look.

Thanks for your reply, this is the link for Rick Piper's Viking - I'll look out the links for the Avro Manchester and Lancaster and send those on too:

https://flyawaysimulation.com/downloads/files/3059/fs2004-vickers-viking-package-4-liveries/

this is the file name for the Lancaster on Simviation:

LANCBIII.ZIP

Still looking for the Manchester

this is the link for the Manchester:

(dead link removed)

I think I got both the Lanc and Manchester from FlightSim, sorry if confused things

Report on the Vickers VC.1 Viking.

Set elevator trim to +2.0, bring up throttle quadrant and place your mouse cursor over the trim wheel on the LH side to read setting. Tail seems to rise at about 100 KIAS on it's own. Rotate at about 115 KIAS and climb at about 120 KIAS. Required about 4000 feet of ground run at a field elevation of approximately 1,000 ft. MSL. Higher altitude airport and/or high temperature will effect takeoff performance. Make sure that your joy stick is calibrated(Advanced settings) to give you at least 45%(travel) sensitivity and a null zone of less than 10%(travel) for the elevator. Flies nice, stable. Landings worked well with an approach speed of about 110 KIAS.

Notes
Actually took off by itself with +3.0 elevator trim. Altimeter seems to read inaccurately. At 16,000 ft. it reads about 300 high. I could not get the fuel panel to show.

➡ http://en.wikipedia.org/wiki/Vickers_VC.1_Viking

Yes, that worked a treat, exactly as you said and to prove it I took off from a rather shorter strip, Gibraltar, from which my wife and I flew in 1954. So I knew it should have been able to manage, and it did - unlike several Shackletons that finished up in the sea!

I then did the same on the Manchester and it performed properly, the tail came up sooner than on the Viking and rotate was slightly lower.

On this basis I applied the same trim to the Lancaster but although the tail lifted it would not rotate at any speed, as it disappeared into the countryside having run out of runway! I didn't try a different trim as I figured what was working for the Manchester should work with the Lanc. I tried about 10 degrees of flap with no improvement in performance.

The Lanc came with a panel for a twin-engine aircraft so for greater realism I substituted the panel from a York which is probably much the same. I don't think this made any difference.

Starting the engines on the Lanc was a bit of a pain and they were less than keen on the twin panel but came up ok with the York panel.

I wonder where I am going wrong?

have you tried stroking the airplane in a soothing way, and saying supportive nurturing things to it?