Model: Kazunori Ito (Jp)
Aerodynamics: Yahia al-Wajid (Es)
Quick install:
Just copy the folder with the .air, .cfg, textures, sound and panel for the X35-C into your aircraft folder for MSFS-9/FS2004 as usual.
In the Panel folder are the Gauges for this airplane, unZIP these gauges and copy them to your FS9 Gauges folder, as usual.
Quick flight:
Keep the brakes . on - his model crawls...!
Press F8 to lower the flaps, open the engine doors and tilt the engines for a short take-off.
Apply throttle with care!
Press F6 several times, or for the brave of heart press F5 to close the engine doors and bring the flaps in the upward position.
The X35 has a stealthy configuration and remains within the sub-sonic regime, however in dives it could pass Mach 1. Should you be in dire need of higher speeds, just change the .cfg "tuning" for "parasite drag", now 0.36 and change it to for instance 0.28... (For extreme speeds the MOI must be changed accordingly).
Quick landing:
Reduce throttle, lower airbrakes if necessary to reduce speeds.
Upon reaching 130 knots press F7 once to reduce further and tilt the engines slightly. By pressing F7 several times (or F8 once) the flaps come out and engine doors are opened for in-flight hovering. With 3 notches flaps you can easily approach your landing target with about 40 knots. Upon closing in apply more flaps. Be careful.
With full F8 (flaps) the horizontal velocity will be near zero knots in light winds... You now can juggle with throttle, stick and rudder like a helicopter to pinpoint your landing position with a margin as large as the airplane itself. If you do this procedure gently without abrupt movements it is like the real thing!
REMARKS
Unfortunately Mr. Ito couldn't be contacted by e-mail.
His model doesn't allow for less flap settings than 8, having the engine doors and appendages connected to that key. Parking brakes appear not to function.
When I discovered the original model (X-35B) it became apparent, that the rather wide range of velocities also introduced instability at lowest speeds, pitching up and smearing off. Also cruise flight trimming appeared difficult.
From my experience with the V22-Osprey I introduced my mathematics to Ito's model and aircraft configuration, changed the .air file [1101] accordingly as to obtain maximum possible stability and manoeuvrability. Particularly elevator pitch to keep things under control at near zero speeds required attention, as well as yaw for rudder. This implies that you should not use rudder in normal flight! The airplane should not be flown with 'coordinated aileron-rudder'... Aileron and rudder must be used separately for more realism. Use the controls always gently and not abruptly.
Also drag and pitch for the airbrakes (spoilers) were adjusted to prevent the rather usual nose-diving. Their "attack" can be tuned in the .cfg file by setting the degrees.
Nextly it showed that 3 or 4 flap settings would also have done "the trick" and make this beautiful model hover and fly away from it. However the splendid model from Mr. Ito is very detailed with many moving parts requiring more options.
Hence I assume that these improvements have Mr. Ito's consent as to freely distribute this aircraft for experimentation only.
As to discriminate this revised model from its original it has been called "X-35C" and can be found under "Lockheed" in FS9. The originator however is Lockheed-Martin, so I leave it up to the user to change this in the .cfg file.
By pressing Shift+W (water rudder) the refuel appendage can be expanded.
By pressing Shift+E the canopy can be opened or closed.
Make sure to have the nice Avro Vulcan K2 tanker in the air to refuel...
UNSOLVED AS YET
Parking brakes disfunction. The model crawls away, so you'll need to apply wheelbrakes to keep the plane from rolling. Weight versus power is just one matter. The lack of a model defined parking brake is evident for as far it was mapped universally [cmd + ยท].
The "problem" here seems the slightly too wide range of horizontal and vertical velocities requirements for the X-35C. There are 2 parameters in the .air file that could be used to stop the plane (aside from setting autobrakes etc.), but they conflict with the range of speeds we require. Keep me posted if you know a solution. [yahia786@elite.com]
Minor corrections could be made with "tuning" the "induced drag" factor, which mainly effects taxiing. "Parasite drag" mainly relates to airborne speeds and I use it to tune the Vmax.
HOVERING
FS9 requires >5 knots forward speed for any airplane (not helo) to lift off (or some parameter set thus low as to even make a plane float away backwards... and remain uncontrollable). However having achieved a hovering position, by using the controls and throttle, in light winds, one can even fly backwards. Just put the least possible winds up (in the FS9 Preferences) and see the difference!
When the calculation of parameters for FS9 reaches a zero value any model becomes fairly uncontrollable, as if it were a puppet loosing one of its strings to be pulled. Bear this in mind when applying rough braking or pitching up and down too much during hovering and making stalls. However with my "aerodynamics" you can often recover from this provided some altitude is available. Retract flaps, full throttle and counter-rudder. Make sure your pitch is flat to slightly nose up when at lowest of speeds.
EDITING
For the daring and Note-Bloc experts here are some considerations:
Make a backup of the X35C folder and its content! You may need it...
Open the "aircraft.cfg" file with Note-Bloc or any other ascii text editor.
In general: nose diving airplanes require a correction from the [airplane_geometry]:
"wing_position_apex_lon" usually needs to be changed a point (f.i. 7.0 into 8.0).
"wing_area", "wing_span" and "wing_root_chord" are defining for most of the flight characteristiques. To make the X35C hover in FS9 we need exceptional values...
Just change the X35C "wing_area" from 2120 into 2650 and fly...
Then change "wing-span" from 104 to 106 and fly...
Finally change "wing_root_chord" to 27 and fly....
Should you find a setting you like and encounter high speed instability, then change the "empty_weight_MOI" for roll (sideways oscillation), pitch (buffeting) and yaw.
The larger the wing the higher the MOI. Too high "freezes" manoeuvrability though.
Got it ??!
Happy landings! (If you still can with the above parameters of course...)
May this contribute to better airplanes for the fine FS9 simulator.
