Reverse Thrust

[Reddog]

Is there a way to increase the reverse thrust on the default C208B so it will move back ward??

[bstolle]

Download the new FDE from simviation.com or flightsim.com and you can taxi backwards (besides having a much better PT6 simulation as well)

[Reddog]

Download the new FDE from simviation.com or flightsim.com and you can taxi backwards (besides having a much better PT6 simulation as well)

That's what I have and it doesn't move backwards.

[bstolle]

Weird, just tried and even at MTOW she moves backwards. Looks like a throttle calibration issue and you don't get full reverse thrust.
Check with the tooltips enabled. At max reverse the throttle tooltip should read 'reverse 30%'
R U using SP2 or Accel ? The new FDE has been tested only with Acceleration....

[Reddog]

Weird, just tried and even at MTOW she moves backwards. Looks like a throttle calibration issue and you don't get full reverse thrust.
Check with the tooltips enabled. At max reverse the throttle tooltip should read 'reverse 30%'
R U using SP2 or Accel ? The new FDE has been tested only with Acceleration....

using SP1 and SP2, no accl. thottle tooltip says that. checked other turboprops with reverse and they all work.

[bstolle]

using SP1 and SP2, no accl. thottle tooltip says that. checked other turboprops with reverse and they all work.

Then it's most probably that you don't have acceleration installed as this definitely improves engine/prop behaviour.
What you can do is to increase the reverse thrust in the cfg file.

[GeneralEngineData]m
min_throttle_limit = -0.30

Just increase the min_throttle_limit up to -100%

BTW, reverse does work but it doesn't necessarily means that you can taxi backwards...

[thunder100]

A big trigger of Reverse trust on Prop's is here

[propeller]
fixed_pitch_beta = 0
low_speed_theory_limit = 80
prop_sync_available = 0
prop_deice_available = 1
prop_feathering_available= 1
prop_auto_feathering_available= 1
min_rpm_for_feather = 400
beta_feather = 88
power_absorbed_cf = 1
defeathering_accumulators_available= 0
prop_reverse_available = 1
minimum_on_ground_beta = 15
minimum_reverse_beta = -15

But be careful with it can have odd other effects

Roland

[bstolle]

A big trigger of Reverse trust on Prop's is here
[propeller]
minimum_reverse_beta = -15

Not really, as the advance ratio is extremely low at that speed and hence the effectiveness very low regardless of the blade angle.
Especially with the new 208 FDE which has a completely new and much more realistic prop.

[Reddog]

Then it's most probably that you don't have acceleration installed as this definitely improves engine/prop behaviour.
What you can do is to increase the reverse thrust in the cfg file.

[GeneralEngineData]m
min_throttle_limit = -0.30

Just increase the min_throttle_limit up to -100%

BTW, reverse does work but it doesn't necessarily means that you can taxi backwards...

I know, it does work in slowing the a/c down on landing. Will try your suggestion.

BTW, does Static Thrust have anything to do with it?? The reason I ask is that on my other a/c that do work the ST= is a lot higher than on your 208.

[bstolle]

BTW, does Static Thrust have anything to do with it?? The reason I ask is that on my other a/c that do work the ST= is a lot higher than on your 208.

ST is realistic, but works in the opposite direction (when talking about moving backwards), so increasing ST would actually counter reverse thrust created by the prop.

[mal998]

Use number shown below and she will back up very nicely using F2 key:

prop_reverse_available = 3 //1 unfortunately MS does not always remark some of their parameters accurately

the higher this number the faster she will back up. if you have a rudder control you will be able to steer her R/L backwards. use F1 to disengage. be careful using brakes when backing up she will end up on her tail.

[bstolle]

That's the perfect solution !!! Thanx a lot for that one
Every other mentioned solutions has the serious drawback of screwing up Ng, Np or both.....

[Reddog]

Use number shown below and she will back up very nicely using F2 key:

prop_reverse_available = 3 //1 unfortunately MS does not always remark some of their parameters accurately

the higher this number the faster she will back up. if you have a rudder control you will be able to steer her R/L backwards. use F1 to disengage. be careful using brakes when backing up she will end up on her tail.

That did it works now. Thanks for that tip.

[mal998]

Happy to help.

[napamule]

Trouble is that any wind, even 5 kts, will 'hold' the ac where it won't move in reverse sometimes. The solution lies in the amount of 'maximum_torque' available.

[turboprop_engine]
maximum_torque= 15900.000 //orig=10614.000 //Max torque available (ft-lbs)

THIS is where you control how effective the reverse thrust is going to be (to overcome wind, uphill climb, cnt pt drag, etc). The line above is the 'important' one as far as how MUCH reverse thrust you are going to get (thus 'overcome' wind, etc). Try it and see. It's NOT the 'static thrust'. Static thrust can be -99999.000. No matter.

Other Tips:
*Adjust the 'maximum_torque=x' value until you get ac to move easily at the above 'min_throttle_limit' value (in (General_Engine) section-usually '-0.14' but can be as much as '-0.39' or so). It's all easier if you have a gauge that shows % of power (throttle) to 'see' 'min_throttle_limit'. Using F3 to reduce amount of 'min_throttle_limit' will allow some 'control' of how fast ac moves. When torque is too much you can reduce the min throttle limit (trial & error). Play one against the other. Every model is different.

*When you are in reverse thrust and press F1 you will jump forward 30 ft with Turbo-Props especially. To prevent this, press F3 (2 times), F2 (2 times), back & forth, about 3 times and ac will not jump.

*To prevent tail strike due to brake while moving in reverse, make sure that the value of 'empty_weight_CG_position' is at least +1 more than 'reference_datum_position' value (it's longitudial value). This can be +2, or +3 more. Trial & error will determine which value works best. At any rate, this is where you adjust for no tail strike due to braking when moving back in reverse thrust. Not cnt pts or moving engines or fuel tanks. OK? OK! Happy reverse in FSX to you all.
Chuck B
Napamule