HOT START ALWAYS!

[juanco 0]

Hello guys! I bought the citation the same day it came out and its a lovely, but every time i try to start the engines theres a hotstart and is keeping the engine parameters above the red line, I´ve read the manuals and folloed the steps of the checklist and still I´m getting this behavior

 

Any help will be really appreciated!!!

 

Juan

[~Craig~ 10]

Yes, I am seeing over-temps on the ITT on most starts too.

 

Another one for the bug list!

[Guest BeaverDriver]

Guys, just check the manual one more time real quick. Typically you're allowed a much higher max temp during a start than would normally be allowed, and I think I read something somewhere in the manuals about that. I thought max ITT was something like 780 for start, but then 710 for normal ops. I could be out to lunch on that, but have a quick look and see if that's not the case.

[~Craig~ 10]

Guys, just check the manual one more time real quick. Typically you're allowed a much higher max temp during a start than would normally be allowed, and I think I read something somewhere in the manuals about that. I thought max ITT was something like 780 for start, but then 710 for normal ops. I could be out to lunch on that, but have a quick look and see if that's not the case.

 

Hey Glenn, you're probably right on those figures (I'm not close to the sim at the moment to check), but the issue with the starts is that Carenado have put the red line in, on the ITT gauge (whether it's marked at the correct temp I'm not sure), and on at least some of my starts, it's exceeding that red line.    Perhaps we've been introducing the fuel too early?    I've been bringing it in at 13% N1, when the rotation really starts to slow.

[JRBarrett 3,034]

I don't own this add on (yet), but something is not right if you are getting those kinds of temps on start. The JT15D engine normally starts very cool compared to many other turbojet engines used on small business aircraft. I have run them many times for maintenance, and rarely see peak EGTs much above 450-500 Celsius on start - and often much less.

 

On a battery start, max motoring on the first engine started will peak at about 13 or 14% N2 at the point where fuel is introduced.

[Guest BeaverDriver]

@Craig - yeah, there should be a thin red line at peak ITT that's allowable for hot starts, HOWEVER...

 

@Jim - thanks for this. It seemed awfully hot to me too even if it is allowed. Appreciate that input.

 

Craig, we need to try waiting until the turbine just won't spool any faster before introducing fuel. If it still spikes as it's doing now, this needs to be reported to Carenado. That's a major bug then to see it go that high, and I'm certain Jim is correct on this that it's way too high. If it's not technique on our part, then yeah, that needs to be fixed.

[~Craig~ 10]

@Craig - yeah, there should be a thin red line at peak ITT that's allowable for hot starts, HOWEVER...

 

@Jim - thanks for this. It seemed awfully hot to me too even if it is allowed. Appreciate that input.

 

Craig, we need to try waiting until the turbine just won't spool any faster before introducing fuel. If it still spikes as it's doing now, this needs to be reported to Carenado. That's a major bug then to see it go that high, and I'm certain Jim is correct on this that it's way too high. If it's not technique on our part, then yeah, that needs to be fixed.

 

I've just got home and will try a start where I wait until the fan won't spin pu any further, and then I'll introduce the fuel, and take a pic of the sim with the ITT at it's peak.      Gimme 20 mins!  :smile:

[~Craig~ 10]

 .....the result....

 

So, I ran from Cold & Dark, operated the starter and waited until it maxed out;  that was at 14.2% N1.    I introduced fuel, and the ITT peaks so high it literally goes off the gauge scale (which maxes at 800 degrees).

 

So, definite bug here.

 

 

This is moments after introducing the fuel.  ITT goes straight off the charts, over 800 degrees.

[Guest BeaverDriver]

Well, not any more it's not. You no longer have an engine to overtemp !

 

That's nuts. OK, I'll fire off an email as well so it (better!!) gets their attention.

 

With that and the readout on the HSI, I'm asking yet again, how do things like this make it to release? These things had better be fixed or I'll end up having to take back all the nice things I was going to say about Carenado. Jeeez.

[juanco 0]

thats the exact image Craig, even when I start a flight its over the max temperature! Its a bug definitely!!!!