Speed problem E3/KC135

[solowing]

I've looked elsewhere in this forum, and haven't found anything to cover my problem (if anyone else sees it, hit me with the blunt nose of the KC and link me).

I just downloaded and installed the E3 and KC-135 models from the HJG website. They're wonderfully done, and everything seems to work except for the speed. It took me all 11,100 feet of runway at Tinker AFB in game to get the plane to even rise off the ground. At full power, the engines seem to want to take their sweet time to even get me up to 350 knots. After playing with fuel and payload values, with no change, I tried editing the cfg.

I've looked in the aircraft.cfg file, and tried adjusting max weight and thrust values, and I get no difference. Unloading 3/4 of my fuel and all but my eight in payload makes the aircraft get off the ground only about 500 feet earlier. I'm not sure if the thrust values or the aileron values would have done anything, as my experience in editing cfg files is slim at best, but I thought I'd give it a whack before I called in the upper management on this one. I have since restored the CFG files to their original, un-tampered with condition.

If anyone has any ideas as to how I can make these models fly as they should (or at least takeoff nicely) I would be much appreciated.

[aerofoto - HJG Admin]

Firstly .... if you've only "slim" experience with FDE modification then (in all due respect) I recommend you don't edit anything.

You may only make things worse !

Secondly .... and performance-wize .... "IF" you're using the turbojet powered "KC135-A" then it will use a hell of a lot of RWY. With a full load .... or overload (up to 300.000LBS MTOW .... though 125,000-261,000LBS is/was more typical) you can expect the T/O run to be unusually long .... that's quite normal for these aircraft .... in fact the USAF RWY/field requirement for a KC135-A was no less than than 10,000-13,700ft depending upon loadings.

The fanjet powered E3 aircraft are quite heavy too .... so .... don't expect the same performance as observed with our civil B707/720's. Again .... that's quite normal.

The modern turbofan powered aircraft should be less RWY demanding though.

A number of things I do recommend are as follows ....

1. Read my B707 PANEL INSTALLATION & HANDLING NOTES thread on the ABOUT HJG AIRCRAFT forum page .... particularly all performance related advisories. Whilst this information is actually intended for our civil B707/720 range much of the same procedural advice also applies to our military C135 range.

2. Prior to T/O set a few degrees of Elevator Trim.

3. Prior to commencing the T/O you should .... with the brakes locked "ON" .... run the engines up to a very high EPR value .... and once that's attained then release the brakes to begin the T/O roll. This procedure is probably more critical for "KC135-A" and other turbojet powered military C135 versions. With these earlier turbojet powered aircraft our B367-80 panel should be used .... and .... when spooling up the engines to T/O EPR the Water/Methanol Injection System switches on the Main Panel .... should be activated in order to boost engine EPR performance and thus assist ("somewhat") the T/O roll. When max engine EPR is attained 4 lamps, located above these switches, will illuminate .... and the T/O roll then begun. At least that's the way I do it and I've not encountered any problems at all .... other than a lonng T/O run .... these aren't short field aircraft. Later fanjet powered aircraft versions aren't equipped with this Water/Methanol thrust augmentation feature .

4. Consider rechecking .... and recalibrating if necessary.... your joystick/throttle or whatever system of control device/s you currently use. In particular be sure your throttle is actually giving you "FULL POWER" according to however it's calibrated.

Hope something here will be of some assistance

Mark C
AKL/NZ