Parts & Vessels Solid fuel engines not producing reported thrust

[ArmchairGravy]

Reported Version: v0.2.1 (latest) | Mods: none | Can replicate without mods? Yes 
OS: Win 11 | CPU: i7-8700 @3.2GHz | GPU: GeForce 1050Ti | RAM: 16GB

 

Hammer engine shows TWR of 1.65, but when launched it does not leave pad.

Edited February 1, 2024 by DibzNr

[hatterson]

Through my testing I found that the Thrust Limiter is double applying.

If you set it at 50% instead of taking 198 kN and going to ~99 it instead halves it *again* resulting in ~49.5

If you set it at 80% instead of going to ~158 it multiplies it by .8 again and results in ~126kN.

This affects all of the SRBs that are used as engines (Thumper, Hammer, Flea, Kickback, and Clydesdale). It does not appear to affect throttleable engines nor does it affect the Sepratron or the launch escape Bottle Rocket.

To reproduce an example you can follow these simple steps:

• Create vessel consisting of a Tin Can mounted on top of a Hammer SRB
• In VAB set Hammer thrust limiter to 25%
• Launch vessel.
• Right click on Hammer to pull it up in parts manager and click activate
• Notice that thrust peaks at ~12.4kN as opposed to the expected 49.6kN

[DibzNr]

It seems that the the issue is with the thrust limiter itself, it seems to be completely off with what percentage of the full thrust it reports to be

[MechBFP]

The title should be updated to indicate it impacts all SRB's lest someone doesn't read this bug report properly and only fixes that one.

[ArmchairGravy]

On 2/2/2024 at 8:12 PM, MechBFP said:

The title should be updated to indicate it impacts all SRB's lest someone doesn't read this bug report properly and only fixes that one.

Done.