Hi Edwin.

The change I made to the engine data is as follows:

[TurbineEngineData]
fuel_flow_gain= 0.003
inlet_area= 18.000
rated_N2_rpm= 29920.000
static_thrust=17400    //15500
afterburner_available= 0
reverser_available= 1
ThrustSpecificFuelConsumption = 1
AfterBurnThrustSpecificFuelConsumption = 0

As you can see, I tried giving the engines 17400 lbs of thrust (information gaied from ^*wikipedia) that say: Eight models comprise the JT8D standard engine family, covering the thrust range from 12,250 to 17,400 pounds-force (62 to 77kN) and power 727, 737-100/200 etc...

Mark

^*I know wikipedia can be wrong, but I'm sure I saw this information elsewhere to back it up. ;)