**OVERSPEED** and **STALL VLV A OPEN**
Fly-Harry-Fly last edited by
What a great aircraft. But quite sensitive.
I love this little bumblebee. It takes a while to get used to the whims of this aircraft. For me, it took quite a while to complete a full flight, from takeoff to landing. Everything always looks so simple on youtube. But some points make me wonder. I don't know if it's me or the technology of the aircraft.
Upon reaching altitude, I turn on turbine gas temperature mode (TGT) in the Thrust Modulation System (TMS). I set the TGT temperature to 820°C. This protects the tubine from thermal overload. This works quite well. But the airplane becomes so fast that it destroys itself. So you can only cruise with airbrakes or you turn off the TGT mode. With that you can't use it for anything.
Am I doing something wrong?
Since I could only fly the plane in sync mode for the above reasons, I had to manually control the thrust. But that is sooooo sensitive. One millimeter too much and the plane destroys itself by overspeed. One millimeter too little and you get problems with the autopilot.
A red warning light -AP- lights up, the AP switches off, there are annoying alarm signals and the yokes start to shake. I think that is a stall warning. Not sure though. And even when you accelerate, the annoying alerts don't go away. No idea how to get them out.
What am I doing wrong? Does anyone have any ideas?
TGT at 820 is not suitable for cruise as you have identified you will overspeed. You don't need to deploy the airbrakes to manage your cruise speed as the TMS can be set to manage your thrust and therefore help you manage your airspeed.
You will see a manual digit counter just below the TMS which you can use to set your TGT temperature, by default this counter is set to 820. Here are some settings you can use as a guide which the Just Flight developers have previously shared:
- Place the TMS in T/O mode for take-off and initial climb. You can change the manual digit counter (using your scroll wheel) at the top of the TMS to change the prescribed outside air temperature and therefore setting a 'flex temperature', if you're unfamiliar with flex temperature's you can just leave this as is for now.
- Shortly after initial climb, you can turn on TGT mode on the TMS and set it to 820 (default value) until ~15,000 ft.
- After you pass ~15,000ft you can set TGT to 840 by scrolling the manual digit counter just below the TMS.
- Once you reach your cruise altitube you now need to set a TGT that is suitable for cruise, this will depend on your altitude, aircraft weight and the speed you wish to maintain. You can start with a TGT value of ~740 but I have had to set values above and well below this to maintain a certain cruise airspeed and definitely not overspeed.
Note, once you scroll to a new TGT temp you may need to switch TGT mode back on in the TMS.
Sorry I can't help you with point 2 as I am unfamiliar with this issue.
Fly-Harry-Fly last edited by
Thank you very much. The answer already helps me. The TGT cruise mode is a little illogical to me. The mode and the speedlimitations are not coordinated at all. But if the aircraft was designed that way, then that's the way it is. Now I know that you have to lower the TGT temperature so much. Thank you.