Engine Start - Fastest Possible

[Caldera]

Hey all,

I knew about duel engine starts a couple of years ago, but I just started playing DCS more and finally opted for the Apache.  I guess I never really thought to hard on the whole process, the goal was flight.

So...

The engine start switches have 3 positions:  START - Off - IGN ORIDE

I was trying to set them up using a Virpil Controller (Sharka-50 Panel) that I have.  I was using two, two position switches that are maintained (ON - ON) using one switch for each engine starter.  I did not realize that in the DCS keybinds you can only map two positions of this switch.  These positions are START and IGN ORIDE.  So I mistakenly mapped START and IGN ORIDE, when I had intended to map START and OFF.

Now after about a few trial starts I noticed that the both engines began to spool up as soon as the APU reached pressure/speed.  It was a WTF moment for me, but that must be how it is supposed to work.  Because I knew no difference at the time.  So what I would do is start the APU and then after reaching about NP 25% on both engines I would flip both switches to START and then advance the throttles to IDLE.  Both engines would start simultaneously.  With both NP in the green at 67% I would advance the throttles to the FLY position, stop the APU and away I would go.

After a bit of time, I noticed ENG1 OVERIDE and ENG2 OVERIDE or it would say ENGINE 1 START and ENGINE 2 START in the Advisory screen.  So another WTF moment or two followed.  Soon after is when I noticed that the starter switch had indeed three positions, but I was only selecting two of them on the Sharka-50 and I was maintaining the switch in position.  So depending on how I had left my switches, resulted in different messages. 

Things were not right...

If you map a keyboard keybind to these start switches and press that key the switch will move to the desired position.  However, the switch will return to center as soon as you release the key.  Works the same for START and IGN ORIDE.  This also works the same with a mouse click, which is most likely how it really works in the real Apache.

To start the engines only a momentary key press is required for an engine start.  But to do a purge, then IGN ORIDE must be held the entire time of the purge.  Obviously, for use here an ON - OFF- ON spring return to center switch would be ideal.

I am not sure why in a simulation you would ever need to do a purge, failed start maybe.  I have not gotten that far into the Apache.

So through all of these trials and mistrials I figured a way to start both engines quite a bit faster than starting one then the other as per procedure.

 

FAST ENGINE STARTS:

Both switches held in IGN ORIDE

Start the APU, as soon as the APU reaches pressure/speed both engines automatically will spool to NP ~ 25%

Flip both switches simultaneously to START (I use a VoiceAttack keyboard macro that holds the switches in START for .5 seconds then releases them so I use the second position of the same physical switch on the Sharka-50 as IGN ORIDE)

Advance both throttles to the IDLE position (I use two buttons on the Sharka-50 for this)

As soon as the rotor begins turning advance both throttles to the FLY position  (I use two axis on the Sharka-50 for this)

Wait for both engines NP ~ 100%

Stop the APU

 

For purests?  Just do it the right way!

Caldera

 

 

[ShuRugal]

I believe it's been stated that the APU in the real thing does not have the airflow output required to spool up both main engines to self-sustainment RPM simultaneously.  If the simulation of that ever gets fixed, this would break the "start both engines at once" thing.

 

It's been my experience that even starting one engine at a time, you can get the helicopter physically ready to fly faster than the INU alignment completes.

[Leg2ion]

I think I'm in agreement with @ShuRugal, and from what I can recall FRCs would elicit a single engine start process.

 

Makes it pretty pointless if the INU isn't aligned and you don't have maps/GPS on line, as you then have to wait regardless, or spend more time when inputting waypoints. 

Not a purist - just makes more sense...

[Caldera]

Yep!

I think I bought the Apache the day it came out, and before that a couple of months I bought the Huey so that I could get used to helicopters.  Maybe, by the second day I had realized that I could start both engines simultaneously.  This idea came out of a YT video, most likely by Casmo where he talked about it briefly.  As I recall badly, he kind of said you could possibly start both engines simultaneously, but because of the extra wear and tear and by procedure you (he) didn't.  He also said that he had never done it IRL.

For my part as far as the alignment goes, the Apache does just fine finishing the alignment in flight.  This is opposed to other aircraft in DCS, example the A-10C where you might have to rewind a bit.  A vast majority of my time is spent in SP training, and as such a vast majority of my flights the alignment finishes in the air.  As soon as the engines go green I take off.

 

On a side note, I don't know how many use the Sharka-50.  It's lay out really is based somewhat on the KA-50 Black Shark, but it works otherwise just great for many other DCS aircraft.  I use two axis for all my helicopter throttles. 

One the of the changes that I did notice is the Apache throttle response has changed.  In the past, once I had the engines started I would advance the throttles to maximum and this would result in NP ~ 101%.  Because I had not played in awhile and a few patches came and went the throttle response had changed.  Now, I found out that pushing the throttles to maximum would result in NP ~ 115% and an overspeed alarm.  This required me to only push the throttles as far forward and tune them to reach NP 101%.  This actually became a bit tiresome for me to repeatedly do. 

So, I modified the curves so that pushing the throttles to maximum only resulted in reaching the FLY position and not going beyond.  This way shoving the throttles all the way forward only results in NP ~101%.  This is about 80% on the Sharka-50.  If you are you axis for the this function it might be useful to have this knowledge.

[Leg2ion]

4 hours ago, Caldera said:

Now, I found out that pushing the throttles to maximum would result in NP ~ 115% and an overspeed alarm

I'll check mine but I only get overspeed if advancing the power levers too quickly. I have mine bound to my Warthog Throttle slider, so find if I move them to mid, stabilise, then full I get no issues. Will get back to you.

[Leg2ion]

Hi @Caldera So checked mine - full throttle - 101%. When you say 115% - is it a transient reading and then settles back down to 101, or maintains 115%? If the latter, not quite sure how you're achieving 115% as the engines are governed and controlled to maintain 101 by the DECs. When your physical throttles are set to max where do your in game throttles sit - should be at 'Fly'.  Only other thing - are you going into lock out - which would remove the automatic governing?

 

Update. Yep - just pushed my throttles into lock out and achieved 116% Np with associated overspeed warnings/bells/whistles.... 

Edited March 23 by Leg2ion
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