FA On vs. FA Off Data

Frustrated with a lack of information about the differences between FA-On and FA-Off, I decided to simply gather my own. I drove my trusty rusty Viper IV about 70km out of the station, and filmed myself performing different actions. I then popped that footage into windows movie maker so that I could use the time-stamps to accurately measure the passage of time, instead of relying on a stopwatch that's subject to my own reaction time. Here were the results:
Flight AssistMovementAcceleration m/2^2
onforward38.6
offforward45.1
onforward+up+right33.6
offforward+up+right89.0
onretro30.4
offretro41.6
onup+right32.3
offup+right48.8
onup+right retro81.3
offup+right retro48.6
onvertical29.2
offvertical26.8
onvertical retro77.9
offvertical retro34.3
onforward+up32.0
offforward+up80.1

*I also measured pitch in the blue zone with fa on and off, but they were within 5% of each other, so I'm going to assume there's basically no change

Things of note:
1) When FA is on, the vertical thrusters are apparently extremely good at getting rid of velocity that's off angle from your current heading. Going from stationary to full vertical was unimpressive, but going from full vertical to 0 was very quick.
...

Noticed this one . along time ago - it forms part of my hot docking technique when coming in off angle - ie FA/off boost until about half way between edge of station and the letterbox, zero throttle, pitch nose to face station, then FA/on at about 1/3-1/4 of the way between the outer edge of the station and the letterbox - it is a very tight turn, and my Anaconda tends go through the slot perfectly, usually docking in under 50 seconds form the 7.5km mark.

Thanks for the effort to get those figures, by the way, very interesting. Some of those FA/off figures are larger than I thought... By a lot!

Z...
 
Noticed this one . along time ago - it forms part of my hot docking technique when coming in off angle - ie FA/off boost until about half way between edge of station and the letterbox, zero throttle, pitch nose to face station, then FA/on at about 1/3-1/4 of the way between the outer edge of the station and the letterbox - it is a very tight turn, and my Anaconda tends go through the slot perfectly, usually docking in under 50 seconds form the 7.5km mark.

Thanks for the effort to get those figures, by the way, very interesting. Some of those FA/off figures are larger than I thought... By a lot!

Z...

Heh, that's exactly what I do when I'm coming in hot in my trutter. D rated thrusters are pretty drifty :)
 
Ready to hate being thorough?

The thruster placement and weight/engine class ratio of each ship causes these results to vary dramatically. If you want a full picture, you're going to have to test each ship individually, because they all have different flight profiles in FA-OFF.

I think I know what Frenotx is going to be doing for the rest of the month....

This is so true, and the reason why the Asp X has a tendency to belly-flop (angled downward-facing thrusters) and the FdL doesn't (bottom thrusters point straight down). Weirdly, the Python has a similar downward-facing thruster arrangement to the FdL, but it struggles more with vertical thrust. May just be due to the increased mass, though.


Very handy information, Frenotx! This will be helpful for all of us combat pilots! :)
 
Last edited:
This is so true, and the reason why the Asp X has a tendency to belly-flop (angled downward-facing thrusters) and the FdL doesn't (bottom thrusters point straight down). Weirdly, the Python has a similar downward-facing thruster arrangement to the FdL, but it struggles more with vertical thrust. May just be due to the increased mass, though.


Very handy information, Frenotx! This will be helpful for all of us combat pilots! :)

I suspect that the thruster placement is strictly cosmetic. I'm pretty skeptical that FDev's flight dynamics are actually a result of modeling the thrusters. More likely, the flight characteristics are simply baked-in.
 
Last edited:
The lateral and vertical thrusters in the clipper are extremely weak in FAOFF, and for a long time I've been using FAON to normalise my approach and remove unwanted sideways motion while closing in towards the mailslot before switching FAOFF for the landing. I never felt like I needed to do that with any other ship, but the difference when bleeding off sideways motion was always clear between the modes regardless of what ship I was flying.

I believe the flight model needs those extra powerful thrusters as a cheat to enable the "airplane" like turns in FAON. That's why they're only that powerful when decelerating towards zero.
 
Last edited:
I did some testing a while ago, as a side-project when I was mapping pitch rates with regards to ENG pips.

It seemed to increase degrees per second almost by a set amount(greater % increase in turn rate when base rate is low, lower when high) but I need to do more rigorous testing to confirm

Hence why ships with poor turn rates are almost mandatory to fly FA off (FDL/Viper III out of blue zone, big 3, Fed Gunship) whereas those with consistent turn rates see little benefit.

Overall, the better the lateral performance and worse the turn rate, the more often it's optimal to use FA off, as lateral performance increase is a multiplier and turn rate is additive (possibly)

Right that seems to be what I've noticed as well although I don't know if there's an actual built in physics relationship between lateral performance and FA on/off pitch rate or if FDev have simply created that relationship on an individual basis by ship design choice.
 
I then popped that footage into windows movie maker so that I could use the time-stamps to accurately measure the passage of time, instead of relying on a stopwatch that's subject to my own reaction time.

[...]

*I also measured pitch in the blue zone with fa on and off, but they were within 5% of each other, so I'm going to assume there's basically no change

Great thread. I have carried out similar movie maker exercises at the end of 2.1 Beta in a FAS with g5 dirty drives and then in 2.1 Live for both Courier and Adder (!) with g5 dirty enhanced drives. Unfortunately I'm not sure what has happened to the results, though. I may do more in Beta 2.3.

The 'basically no change to pitch' made me raise an eyebrow, though - see later!

All combined (non straight line) retro accelerations are faster in FA on?
Or do I read these numbers wrong, it's hard to believe (surely even harder to explain as to why this is)?

Yes, this is fundamental to evasion. Evading fixed weapons means presenting your opponent with a target that changes both direction and speed rapidly. That requires both acceleration and deceleration.

FA-on acts as a massive, decelerating, air-brake. There is no explanation in-game as to how our thrusters are significantly more powerful when applying counter-thrust with FA-on than off. But basically if you are flying directly to your right at 100 ms with FA-off, you will get back to stationary a lot quicker if you put FA-on before thrusting left, than if you leave FA-off.

Therefore (although in the more manoeuvrable ships it is often unnecessary to put FA-off to evade) when it really matters, the best evasion will often involve a combination of FA-off and re-engaging FA-on so as to provide massive lateral deceleration, before then beginning the process again in another direction.

Retaining FA-off throughout will often simply result in too much momentum in one direction and stalling while attempting to arrest it, albeit to some extent this is made up for by unpredictability.

P.S. Using your film/time stamp method, a clever player should be able to divine the acceleration of every axis, on every ship. Post that! Lol

P.S.S. Is there any suggestion that these values may be different between ships?

Really, all timed exercises (such as measuring DPS etc.) should be carried out using the vid method after the event. Tapping mobile phone stop watches is way too error-prone!

About the different ships ...

With regard to pitch rate, I've always thought that different ships alter their pitch by different amounts with FA on/off. For example in the Python it seems very marked indeed where in the Vulture it's barely perceptible.

^^I can't imagine trying to drag an Anaconda or Python back on line without at least momentarily putting FA-off. Although I will usually be using thrusters at the same time, I'm pretty sure that there's a significant, straight, 'no thrusters' pitch buff with FA-off and I think Nerwan is probably right about this differing ship by ship.

Although it does seem odd that a ship with the Viper IV's poor pitch should be one of the 'little difference' ones, on that basis.

That's really interesting....

So basically reverski (retro + thrusters) with FA-on is far superior to FA-off which is superior in all other cases, which is probably why it's become such a popular maneuver.

I think as others such as @TuxedoSteve have indicated Frenotx is referring to the superior deceleration of FA-on by his use of the term 'retro'. A straight reverse from a standing start with FA-off will accelerate (backwards) far faster than with FA-on.

These results, which have been generally known by more advanced players forever and that I first saw quantified by Alexander The Grape, are precisely why I'm only using FA-Off about 3-5% of the time I spend in combat and why I scoff at those who insist FA Off all the time is somehow superior (in any other way than flavor).

While the % may be up for debate, I don't personally believe that it's possible to achieve the best possible manoeuvring with either full-time FA-off or FA-on. I've always taken some comfort from the fact that Cmdrs whose piloting I have admired first-hand, such as BreakfastMelon and PoaArctica, appear to agree.

I love watching full-time FA-off PvP vids with fixed weaponry but I suspect it's more of a personal challenge thing for the pilots concerned. Hence why they're often filmed in trollolo ships, to boot.

I did some testing a while ago, as a side-project when I was mapping pitch rates with regards to ENG pips.

It seemed to increase degrees per second almost by a set amount(greater % increase in turn rate when base rate is low, lower when high) but I need to do more rigorous testing to confirm

Hence why ships with poor turn rates are almost mandatory to fly FA off (FDL/Viper III out of blue zone, big 3, Fed Gunship) whereas those with consistent turn rates see little benefit.

Overall, the better the lateral performance and worse the turn rate, the more often it's optimal to use FA off, as lateral performance increase is a multiplier and turn rate is additive (possibly)

I salute "Grape's Guide" and indeed have even summarised your results on this forum, somewhere!

As above, it does seem a bit odd that the Viper IV should not get a decent pitch buff from FA-off, though, bearing in mind its atrocious pitch rate.
 
Last edited:
+1 Virtual Rep

I am an FA off pilot

Regarding blue zone affecting thruster output: were they consistently +5% or was it scattered +ve and -ve?

5% isn't bad...

I remember a video of a commander, in FA Off, putting the throttle in the BZ and again without. With the latter, his lateral thrusters didn't stop him before the letter box but the one in the BZ was OK.

Did I dream that?
 
Last edited:
+1 Virtual Rep

I am an FA off pilot

Regarding blue zone affecting thruster output: were they consistently +5% or was it scattered +ve and -ve?

5% isn't bad...

I remember a video of a commander, in FA Off, putting the throttle in the BZ and again without. With the latter, his lateral thrusters didn't stop him before the letter box but the one in the BZ was OK.

Did I dream that?

With FA-OFF you can't simply put the throttle in the blue zone and expect a result (You are commanding Thrust not Speed) For optimum maneuvering rates you are required to adjust speed until you in the blue band. For example - I can fly the optimum blue zone with throttle at Zero.

@Op, did you do the lateral/vertical tests with analog inputs? The results will differ from digital inputs.
 
Last edited:
By the way Frenotx, did you do these tests with 4 pips in ENG? You didn't say in your OP.

I'm pretty sure that, in general, fewer pips weakens acceleration in FA off (But not top speed) while it weakens top speed in FA on (but not acceleration).


At this point I'm most curious to see if there are large ship-to-ship variations in FA on vs FA off acceleration profiles. I think "boost while trichording with FA off" is always going to be the #1 fastest way to accelerate in any ship, but I'm intrigued by the idea that for normal single-axis acceleration the difference between FA on and FA off may vary between ships.

By "acceleration" I mean moving the speed dial away from zero regardless of flight vector, in case that's not clear.
 
Last edited:
By the way Frenotx, did you do these tests with 4 pips in ENG? You didn't say in your OP.

I'm pretty sure that, in general, fewer pips weakens acceleration in FA off (But not top speed) while it weakens top speed in FA on (but not acceleration).

Fewer PIPS to ENG with FA-OFF will result in a lower top speed. PIP settings basically act like a thrust limiter, it works the same across both flight assist modes.

As mentioned previously, there is a big difference in performance between digital and analog thruster inputs whilst in FA-OFF.
 
Which is a questionable definition when it comes to practical use as in combat situations usually we won't come to a full stop. It could be worthwhile to look at various acceleration "ranges", like from 0-100, 100-200, 200-300 and so forth. If acceleration in different ranges are all the same then we can skip these thoughts. Does anyone know for sure and/or already did such tests?

This is a good point and a very easy one to resolve.

I am currently gathering mats in my Conda for a couple of days but once back in my Courier I can just vid myself going from 0 to 450 without boosting and then break the segments down on the vid.

In fact, I'm quite motivated by this thread to take a look at the various vectors and inputs again.

Come on guys, let's crowd-source this thing. If you already have vid software it's a matter of minutes to leave a station and do a bit of testing. Post your data!
 
This is a good point and a very easy one to resolve.

I am currently gathering mats in my Conda for a couple of days but once back in my Courier I can just vid myself going from 0 to 450 without boosting and then break the segments down on the vid.

In fact, I'm quite motivated by this thread to take a look at the various vectors and inputs again.

Come on guys, let's crowd-source this thing. If you already have vid software it's a matter of minutes to leave a station and do a bit of testing. Post your data!

I am quite interested in this as well but, I haven't the experience with the technical aspects of creating the Vid, and measuring the results. Can we discuss ways of dealing with this?
 
I think as others such as @TuxedoSteve have indicated Frenotx is referring to the superior deceleration of FA-on by his use of the term 'retro'. A straight reverse from a standing start with FA-off will accelerate (backwards) far faster than with FA-on.

But why measure that deceleration instead of backward thruster performance? Given that he listed "Retro" by itself it seems to me like he was measuring thruster performance while reversing, and chose that word because thrusters to move backwards are, AFAIK, termed "retrograde" thrusters.

And measuring that deceleration precisely with thrusters in use seems horridly complicated, to me - you'd have to first accelerate in a direction with full use of those thrusters, then immediately & simultaneously reverse your commands for all 3 thrusters - forward/back, left/right, up/down - and then measure how quickly you come to a stop.

Additionally his data does indicate that "Retro" thrust, without additional lateral input, will accelerate faster in FA-off, as you say.

Hopefully Frenotx can confirm/deny to clarify. :p
 
Noob question: if I'm thrusting at full throttle, in FA Off I continue at that speed indefinitely even after releasing the thrust. Why does this work differently for boost speeds?
 
Noob question: if I'm thrusting at full throttle, in FA Off I continue at that speed indefinitely even after releasing the thrust. Why does this work differently for boost speeds?

It's a change they made in the prerelease beta, purely for balance reasons.

Full (boost) speed FA off was resulting in CMDRs (myself included) doing things like flying backwards in the Viper Mk III faster than anyone could keep up while maintaining fire on pursuers, or drifting in and out of engagement range firing missiles at maximum distance (and before the original missile nerfs this was extremely potent). Basically it made the fastest ship at the time (the Viper Mk III), which was also the best combat ship at the time (only the Cobra and Anaconda were bigger, and only the Anaconda had more firepower) invincible...back when that was a bad thing. It also didn't jive with the dev's vision for combat, which was meant to be less high velocity drifting turrets and more 'dogfighting in space'.
 
Last edited:
It's a change they made in the prerelease beta, purely for balance reasons.

Full (boost) speed FA off was resulting in CMDRs (myself included) doing things like flying backwards in the Viper Mk III faster than anyone could keep up while maintaining fire on pursuers, or drifting in and out of engagement range firing missiles at maximum distance (and before the original missile nerfs this was extremely potent). Basically it made the fastest ship at the time (the Viper Mk III), which was also the best combat ship at the time (only the Cobra and Anaconda were bigger, and only the Anaconda had more firepower) invincible...back when that was a bad thing. It also didn't jive with the dev's vision for combat, which was meant to be less high velocity drifting turrets and more 'dogfighting in space'.

Yes, I can see how this makes sense; thanks for the explanation
 
Back
Top Bottom