[REPORTED and INVESTIGATING]Various remarks

[El Chapo]

Hello there,

Thanks for the latest updates, much appreciated.

Just in case it raises some interest, a few remarks regarding a few remaining issues:

- when you put battery "on" before start up, you should see T7 and CALC lights flashing (self tests). If throttle is not off at that time, CALC light will stay "on".

- the "engine fire" lights are push buttons that can be tested.

- the "emergency landing gear down" is a "pull" command, not a "turn" command". It has a square shape that prevents it from turning around.

- In my opinion fuel dump makes way too much "smoke". IRL fuel dump is more a faint "fog".

- NWS seems to be put "on" by default (or keep its last state) on landing. I should always be "off" and require a pilot input to be turned "on".

- start-up engine temperature is quite "hot". A rule of thumb is temperature = 20*RPM during start up (e.g.: 600°C at 30%). But fuel flow is far better than on earlier versions!

- initial sec. carb. RPM without input at 42% is far too low. From 65% you should see a decrease to around 50% RPM, not that far below in the 40-ish% RPM. Engine might shut off at such a low RPM.

[Galinette]

What do you mean by Tt7 rule of thumb? RPM increases to approximately 60% for the anti surge procedure, and this rule would lead to 1200°C Tt7. Tt7 may not be 100% accurate, but this is a simulated parameter (from full thermodynamic modelling of the engine) and is not "scripted", so we can't apply an average rule here. What I know is, it nearly touches the red zone at each startup and decreases.

Same for Sec CARB RPM, it's in no way scripted and a pure simulation result. The default fuel flow is the parameter here. Maybe it's too low.

 

Besides this, alarm panel is not accurate, and will be updated later on together with better failure modelling. Emergency LG handle too, this is an old thing that requires remodelling how the handle animates so fixing it is postponed, but will happen.

Edited August 4, 2022 by Kercheiz

[El Chapo]

When you check your start up sequence, you check that you have around 200° at 10%, 400° at 20%, 600° at 30%, etc... It increases to around 1000° and then falls back to lower temperatures. I agree with you that you should not expect 1200° at 60%... But it works really well up to 40%.

If you have for example 500° at 20%, you know that you are "hotter than usual" and you prepare yourself for an aborted start up in case of overheat. 

Overheat might not happen, but still, better be prepared... 

Regarding RPM and fuel flow: I'd say that you idle fuel flow is slightly low. It was 15kg/min in normal regulation, while it's usually closer to 18. It might explain the low RPM in emergency regulation. But still fuel flow in emergency regulation is slightly higher than in normal one... 

Anyways, excellent job overall! Nice to see that your mode is still evolving. 

[El Chapo]

By the way, normal procedure checklist says that during engine test on runway before take-off, you must have RPM 95-103% and T7>800°C.

Usual FF is around in 80-85 kg/min at that time. 

I had only 650°C, which is another hint that your temperature model has to be slightly tuned up. 

[myHelljumper]

Hi,

I have logged the obvious issues.

We will investigate the more complex problems like engine temperature.

Thanks.