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#3897034 - 01/17/14 07:00 PM Mission fragging - cruise speed and altitude  
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DarkFib3r Offline
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Is there a good rule of thumb for cruise altitudes and speeds between waypoints? It seems that the mission planner often sets either really fast speeds that burn up too much fuel or really slow speeds that is a little plodding. Is there a general altitude/speed combination that you use for high-altitude missions?

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#3897769 - 01/18/14 10:56 PM Re: Mission fragging - cruise speed and altitude [Re: DarkFib3r]  
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- Ice Offline
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What is a "high-altitude" mission?

I generally cruise up high (20K+) on ingress/egress for better fuel economy. The only time I went to 35K was when we needed go teleport to the front lines and used the afterburner the whole way. Once forward of the FLOT, my altitude would depend on the current situation. I would stay at cruise altitude if I was doing escort, but I would usually go lower if doing A-G work. The only time I would stay at altitude when dropping bombs is when dropping LGBs or JDAMs. biggrin


- Ice
#3897879 - 01/19/14 03:33 AM Re: Mission fragging - cruise speed and altitude [Re: DarkFib3r]  
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DarkFib3r Offline
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Thanks for your feedback. What I am referring to with high-altitude missions is fragging missions that aren't nap of the earth.

When you create a package, it sets some seemingly seemingly arbitrary and variable altitudes and speeds for each steerpoint. I am wondering if there are some solid guidelines for configuring these types of missions so that fuel consumption is respected. For example, set cruise altitude to 22,000 feet and cruise speed to 350 kts. On IP and TGT, depending on mission, set speed to x and altitude to y.

Thanks for the ideas!

#3898284 - 01/19/14 11:47 PM Re: Mission fragging - cruise speed and altitude [Re: DarkFib3r]  
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Hmmm... to be honest, I've never really respected any of these, especially the altitude values. At the very least, maybe the TOT or time over steerpoint for CAP missions but I rarely do them. Also, it seems like it assigns more or less the same altitude blocks for most missions anyway.

I usually fly depending on the tactical situation, so once over the FLOT (or sometimes even before!) I fly as I see fit. I try to conserve fuel when I can, but I usually fly with more fuel than I need in case I need the extra playtime. Don't worry too much about "respecting fuel consumption" --- so what if you had enough fuel to get home if the bandits got you anyway because you wouldn't fight them with your afterburners on? Just remember your joker/bingo and know whether you can stay and fight (and for how long) or if you need to turn and run.

Also, you might've noticed by now that the routes the AI plot out for your flight might not be the best route threat-wise or might not even make sense. I rarely fly the default route, I always tweak to my preference which mostly means diverting due to existing SAM threats.

Good luck!


- Ice
#3898333 - 01/20/14 02:06 AM Re: Mission fragging - cruise speed and altitude [Re: DarkFib3r]  
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Kosmo. Offline
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I don't know what Falcon version you're flying but I'll assume it's BMS. If so, the speeds are not arbitrary, but I understand why they may seem weird at first. The airspeed is calculated so that you stay with your package (where applicable). The Push waypoint will have a low required airspeed to allow for contingencies, ensuring all flights can make it in time. And if you want to hit your TOT you will want to keep at the planned (lower) altitude so that you retain your maneuverability (IAS). Fuel economy does not play a role when planning.

Generally I don't worry about fuel too much. When nothing goes wrong it is always enough in Korea with the short distances. On AG missions IRL you will always take two bags regardless of distance. If you get in a fight as Ice said forget about fuel and the mission, survive, drop everything if needed, go full AB, do what you have to. If you have no fuel try to think about how you can run away. The mentality regarding fuel is this: excluding supercruising don't fly the whole flight trying to save fuel. Start saving fuel when you start or seems you are about to start having fuel problems. Notice though how I said "start saving fuel", not "start thinking how to save fuel", emergency cases like this should be planned for when still on the ground.

Fuel planning for fighter jet missions is not like the airlines. You don't plan the most economical profile so as to take and burn the least amount of fuel possible. Fighter pilots don't have to worry about money spent on fuel and don't really have to worry about performance either. You pick the speeds necessary to do the job (for instance low alt will require higher speeds and consumption is higher either way as the air is thicker), then you calculate the fuel you need for that plus contingencies and load it. Or more accurately you calculate if you need bags and how many, then top all tanks off.

Higher altitudes are not really significant usually, there are few things that can get you at 22k but can't at 35. Fuel consumption is not that significantly lower with Korea's short distances. The radar in AA mode might not be 100% effective when looking down. You might also be making some cool contrails which let everyone in the area spot you from miles away. And as I said you give up airspeed and maneuverability at higher alts if you want to be on time. The only serious reason to go high is if your fuel is really marginal to make it back or something like your engine is dying and you want to have room to glide.

And like Ice I also always edit my route somewhat to avoid SAMs (not too much though if I am in a package). It's also worth noting that SAM threat circles in the UI map might be outdated (by a few hours) or there might be other SEAD or DEAD flights scheduled to work that area that are not in your package. I don't count on either of those though.

In short I'd say, keep the lower speed required to the push waypoint unless you are not in a package (you still can but it's not necessary). Other than that, 350 KIAS which is what is planned in BMS usually, is a very common airspeed flown operationally by fighter squadrons (RL).

Sorry for the rather long post!

#3898690 - 01/20/14 06:56 PM Re: Mission fragging - cruise speed and altitude [Re: DarkFib3r]  
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Kosmo. Offline
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Just to add, low level flights are commonly flown at around 450 KIAS for the ingress and egress, and around 550 KIAS during the attack (though this type of mission is very rarely flown nowadays).

#3900383 - 01/23/14 05:20 PM Re: Mission fragging - cruise speed and altitude [Re: DarkFib3r]  
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- Ice Offline
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Yeah, contrails.... I forgot about that. Excellent post though, Kosmo!


- Ice
#3938382 - 04/12/14 07:59 PM Re: Mission fragging - cruise speed and altitude [Re: DarkFib3r]  
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Gigolety Offline
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Darfib3r I leave a message left by a real Viper pilot on another place. He is talking about the best way to calculate bingo:

It's been a long time since I last flew the '16, so I don't know what the latest software includes. However, I flew all USAF blocks between 5 and 42, and all had a selectable "HOME" mode. We would select the desired destination waypoint on the FCNP, mode select HOME, and would be presented with carets on the HUD for optimum altitude and speeds. This would give you the optimum fuel conservation profile to arrive at (if I recall correctly) 5000' AGL over the desired waypoint, presumably the place you wanted to land. The profile called for a MIL power climb at the airspeed indicated on the HUD, cruise at the indicated altitudes and airspeeds, and then an idle descent to the point above the airfield. In regards to this thread, the power setting was MIL, and that was the most fuel efficient climb.

I had to "no kidding" use this mode one time after hanging around too long after my wingman ejected, arriving back on the runway with 400 lbs of fuel. It works!

The Viper has grown enormously since when I flew the thing .

The Bingo fuel is easiest to use a Rule of Thmb (RoT). The total fuel RoT depends a lot on the mission - CAP, CAS, strike, etc.

I imagine that the newer birds use maybe 15-20% more gas than our old 'prototypes'. We had lighter jets and didn't use a lot of external tanks. The older birds were also cleaner.

I would start with the Bingo fuel calculation. Try 8-9 pounds per mile plus whatever you want at homeplate. So we used to RTB from a hundred miles out with 700 pounds plus whatever we needed in the pattern (we were cleaner, lighter, so it was 7 pounds versus 8 or more like today). We climbed using the HUD and FCC 'range' mode. Descended at just above idle (for wingies) when base TD box was about 3 degrees below horizon line.

On ingress at Red Flag at low alt with two big ext tanks and a buncha Mk-82's, we figured about 10,000 pounds per hour for a decent speed - 480 or 540 knots. So that's about 18-20 pounds per mile.

If you light the burner, all bets are off, so include a minute or so of burner in your calculations - say 1000 pounds.

Gums sends




There is a nice explanation on F-16 C/50 52+ manual about HI-LO-Hi altitude profile calculation or Lo-LO altitude profile calculation. They make an example about fuel calculation based on a mission and the profile you want to keep along this flight.

Basically what the others said in previous message is right there is not too much to say, except that you will keep an higher altitude along your Return To Base flight path and mainly inside friendly territory.


If you are short on fuel and you do not want to land on an alternate or a tanker is not available close to your position you can climb higher than 29.000 ft but be sure that your campaign is in a situation where your team has an airpsace domination inside the friendly territory. You will see that your fuel consumption will drop drammatically.

Speed, as said anything tactical is at more than 450 kts.



Last edited by Gigolety; 04/12/14 08:03 PM.

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#3938516 - 04/13/14 02:34 AM Re: Mission fragging - cruise speed and altitude [Re: DarkFib3r]  
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Frederf Offline
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Try the CRUS HOME profile. It uses the minimum fuel possible to travel to your desired steerpoint (+7000' altitude). It's a MIL thrust climb following the caret followed by a max range level (slightly climbing) leg and then a max range descent. It even tells you how much fuel to expect to have at the end.

One of the Greece F-16 flight manuals has a HI LO LO HI bombing mission profile that has no fooling a 1121nm total mission distance. With the right procedures the range you can squeeze out of the fuel on board is remarkable.

#3939307 - 04/14/14 10:26 PM Re: Mission fragging - cruise speed and altitude [Re: DarkFib3r]  
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toonces Offline
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Just a few things I might add:

I think there is a file in Falcon that specifies altitudes for various aircraft to use in the game as a rule of thumb for planning. I can't remember where it is anymore, but I'm pretty sure I've seen it.

Also, remember that if you're flying in a package, the AI are going to follow the specified flight plan(s). So if you start going off the script, tasked with Strike say, and you miss your time on target, you may find that your SEAD and/or Escort have not yet arrived, or left already depending on whether you are early or late.

Finally, keep in mind that the AI wingmen in your flight will also follow the flightplan when given weapons free. So if you're doing a Strike and your flightplan has you on target at 25k but you've self-motivated down to the deck, when you give the flight weapons free to attack the target they're going to zoom back up to 25k to drop their ordnance. This can be very sad if you've gone low to stay under a SAM threat frown


"A week or even a month for someone basically saying "shucks, this is pants" maybe. But their banhammer only has the forever setting. Gotta set phasers to stun for the localization of female undergarments, not kill yo." - Frederf

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