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Fuel Burn


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I'm not sure if this is what you're talking about, but this is what I heard recently:

The idea, as it was explained to me, is that it is intended to highlight those who routinely come back with excessive fuel loads (therefore over padding their initial onload). I'm not sure what MDS you come from, but in the C-17 world (supposedly) it would highlight those that come back with a significant amount in excess of about 30-40K. It seems like it could potentially encourage someone to make a bad decision down the road...I'm curious what the more experienced guys think.

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Guest PilotKD

Pilot judgement. If you've got a good reason for it, they can't do a damn thing about it. I would give a big, fat :flipoff: to anyone at TACC who bitched that I came back with more gas than I was planned for, again, if there was a good reason. On the other hand, I think some upload more gas so they don't have to use good pilot judgement. There's a fine line. What pisses me off is the Air Force goes from one extreme to the other. All of a sudden now we're concerned about fuel conservation? Give me a break. We fly some of the oldest friggen aircraft on the planet. We're not designed for conservation.

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Whatever it is that you were fearing is here at CHS.

We have little local reports that we have to fill in at Base Ops upon landing including starting fuel, ending fuel, and time spent training. I'm not sure if someone is actually scrutinizing the reports in order to accuse Capt Gas Guzzler of landing with too much fuel, but I think they are moving in that general direction.

I believe that we will have to start using CFPS to calculate fuel required the day prior and then order up that fuel for the tail to even get it that much closer.

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alright, here is what i don't understand about fuel conservation measures. how does putting less gas on board save gas? if you tanker more gas and have extra when you land, thats just less gas you have to put back on, right? i know you reach a point where it costs gas to carry gas due to a heavier weight aircraft, i've just never really been at that point. so is this only a real factor for the strat air types? because as a herc guy it all seems a little silly. AMC SII fuel conservation measures means i can't ask for an extra 5K on board to do pro after a tac ride; it doesnt mean any gas is saved per se, only that additional training was not accomplished. and deployed, i dont feel like i am saving gas since they fill it back up as soon as i land anyway. so if someone could offer some insight i would appreciate it.

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Pilot judgement. If you've got a good reason for it, they can't do a damn thing about it. I would give a big, fat :flipoff: to anyone at TACC who bitched that I came back with more gas than I was planned for, again, if there was a good reason. On the other hand, I think some upload more gas so they don't have to use good pilot judgement. There's a fine line. What pisses me off is the Air Force goes from one extreme to the other. All of a sudden now we're concerned about fuel conservation? Give me a break. We fly some of the oldest friggen aircraft on the planet. We're not designed for conservation.

You know what shitty fuel burn is? Taking off with 160K to go and "supposedly" refuel F-22's in a MOA near Edwards. Only to find two F-18's that take a combined 8.5K offload. Then having to drop the gear and fly back to KSKA with gear down and at FL 230 to burn more fuel to barely make it under the gross weight to land without having a waiver (and the OG didn't want us to "adjust gross weight.")

13.89 on the fuel burn for the TAR.

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Guest PilotKD
You know what shitty fuel burn is? Taking off with 160K to go and "supposedly" refuel F-22's in a MOA near Edwards. Only to find two F-18's that take a combined 8.5K offload. Then having to drop the gear and fly back to KSKA with gear down and at FL 230 to burn more fuel to barely make it under the gross weight to land without having a waiver (and the OG didn't want us to "adjust gross weight.")

13.89 on the fuel burn for the TAR.

Exactly. This is why I say we're not conservation oriented. We burn fuel to get the mission done. Being that our mission is very dynamic and "$hit happens", sometimes you just can't help it. Same thing happened to me out at Edwards about a year and a half ago. We ended up orbiting in the MOA for over an hour with the gear down to burn enough to land back at Edwards because the F-22 had a "Blue Screen of Death" and had to go reboot.

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I have been hearing rumors of this in the tanker world as well! TACC will eventually be using our (block 40.3+) end of mission reports to track how much we're landing with.

We normally land with around 25,000 from most training missions, and from what I've heard that number will be mandated down to 12-15,000 on a daily basis. They're even going so far as to say if you show at the jet and it has more than 5000 extra, you will have to download the fuel rather than take the jet that heavy. YGBSM.

This will get very interesting when we go overseas. Every single trip it seems that the clowns at TACC have mission planned us with less than the required fuel to make the trip, so we end up having our crew chiefs add an extra 20-25k. I can't wait to have to request a waiver to do that in the future.

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alright, here is what i don't understand about fuel conservation measures. how does putting less gas on board save gas? if you tanker more gas and have extra when you land, thats just less gas you have to put back on, right?

At higher gross weights it requires more engine power to maintain airspeed. In other words, tankering gas makes you burn extra fuel in order to carry the tankered gas.

In Herks, you don't want to tanker gas more because it's a performance/payload-limiting issue than a conservation issue.

HD

Edited by HerkDerka
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In Herks, you don't want to tanker gas more because it's a performance/payload-limiting issue than a conservation issue.

Then why do EC/AC/MC's do AR and slicks don't?

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"In Herks, you don't want to tanker gas more because it's a performance/payload-limiting issue than a conservation issue"

i guess that depends on how much gas you're talking about. if i take off at 125K vs 120K barring some unusual temp or pressure altitude it usually doesnt hurt my performance. and thats my point-- AMC fuel conservation SII prevents me from putting on a couple extra thousand pounds even though i think i may need it. so i understand the emphasis on strat air/tanker guys not putting on too much when you are dealing with tens of thousands of pounds. but i have flown maybe 5 missions where the 'costs gas to carry gas' performance data applies. mostly its me wanting more gas and being denied an extra 3 thousand pounds. i just dont understand the logic of trying to order hercs not to keep a little extra on when tankers are flying around with their gear down or dumping.

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This will get very interesting when we go overseas. Every single trip it seems that the clowns at TACC have mission planned us with less than the required fuel to make the trip, so we end up having our crew chiefs add an extra 20-25k. I can't wait to have to request a waiver to do that in the future.

Two.

On a recent overseas trip we added a significant amount 'extra' (no uncommon at all for us) . . . turns out that had we taken the TACC planned fuel load, on one leg we would have ended up diverting and on another, in the ocean. Awesome planning on their part I thought.

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I wonder if the geniuses at AMC factored in the cost of unplanned diverts resulting from tweezer-ass fuel planners. Flying the KC-135 for over 2000 hours, I diverted only once, and probably saved 10-12 diverts because I had sufficient fuel to hold until weather improved enough to land. Planning to arrive with the bare legal minimum will surely increase unplanned diversions. It sounds like Uncle Sam is willing to spend a dollar to trumpet the savings of a dime in this instance. :bash:

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The military in general needs to pay way more attention to the airlines, specifically Fedex, UPS and Southwest. These guys have figured out how to run at min cost and there is no reason we in the military should not either, in fact we owe it to the guys who pay our salary to do so. So running with less gas only saves a few hundred pounds a leg, a miniscule savings but whien multiplied by the number of flights we do in a year saves millions. Anywhere we can run a GPU vs an APU, An Air cart vs an Engine, taxi with an engine shut down after landing or starting the last one up in the EOR will all save a ton of gas when looked at on the grand scheme. Just because a flight here and there has to dump fuel because of a cancelled fighter sortie is not a valid excuse for everyone else to waste gas. 10 diverts out of 2000 hours would have most likely cost a lot less than the amount spent on tanker fuel and holding - pain in the ass maybe but it would have saved money.

With that said sound judgement still prevails. There is absolutely no excuse for ditching in the ocean because someone told you you would have enough, the AIB would be incredibly short. No one needs to tell a pilot how much gas he can have no matter what the reason, on the other hand there is no reason they shouldn't have justification for the fuel the pilot wants. Just because is not a valid answer. It does get sticky if they are going that route where a planner will not under any circumstance give more gas. Figure out how much gas you legally need and add some for crappy weather, just throwing on a few thousand because it would be nice to have is wasting money. Not nats assing your fuel to include training and currency down to the approach and touch and go and then landing at min legal fuel is wasting money. Taking a bunch extra today just because someone you know had to put the gear down and burn yesterday for events out of his control is ignorant. We all owe it to the Airforce and the tax payer to save a buck here and there even if the apparent savings are miniscule, besides it just makes common sense to save gas no matter how small the amount. Airlines figured this out a long time ago, amazing it is taking the military so long to follow suit.

my .02

-j

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Whatever it is that you were fearing is here at CHS.

We have little local reports that we have to fill in at Base Ops upon landing including starting fuel, ending fuel, and time spent training. I'm not sure if someone is actually scrutinizing the reports in order to accuse Capt Gas Guzzler of landing with too much fuel, but I think they are moving in that general direction.

I believe that we will have to start using CFPS to calculate fuel required the day prior and then order up that fuel for the tail to even get it that much closer.

We already have to do this on the west coast.

It actually surprises me that other airframes in AMC are just now talking about this. A little over a year ago an FCIF came out in the C-17 community concering fuel conservation. Depending on how much extra gas a crew wants, a request for a waiver goes up to a 1 star at TACC. There is some room to play and I've actually found that the planners are overly generous!

Someone else asked if tankering extra gas is actually that big of a deal...Yes, it is! When you have the capability to carry more than 200,000 of gas, tankering just to save time on the ground is not worth it (in most cases). I don't have the numbers in front of me, but the extra cost is significant. I look at it this way, if I ever want more than what was planned, and I have a good reason, then I'll make the request knowing I'm right. If the request is refused, then my crew doesn't fly that day. I've never had a request denied (and I've never met anyone that has -- as long as the request makes sense).

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I totally agree with you J, but I don't think planners should tell pilots what amount of fuel they need without the pilot first justifying the needed fuel amount for their mission. The planner should then examining it closely with what they expect (what the planner had plan) and then reconciling it to account for variable(s) not previously considered and the like. I believe this system will be much more efficient. Furthermore, unlike the Airlines and FedEx that flies the same known routes, the military mission is quite different and diverse, and trying to make the AF fuel efficient should consider these variables that aren't present in civilian flying.

Just my two cent as a GA pilot with no military flying experience.

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Then why do EC/AC/MC's do AR and slicks don't?

You're misunderstanding. We're not talking about AR. "Tankering gas" just means taking off with extra gas that you don't need.

HD

Edited by HerkDerka
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i guess that depends on how much gas you're talking about. if i take off at 125K vs 120K barring some unusual temp or pressure altitude it usually doesnt hurt my performance.

It's not a huge change, but it still limits it. The eng changes the told card every 5K. That's not a big deal flying around he flagpole, but summertime at OAIX, I'll take all of the performance I can get.

I understand what you're saying. We don't carry much gas when you compare it to tankers and heavies. What we consider "tankering" hardly ever exceeds 5K and is a far cry from what you'll see in the t-tail world. But Big Blue is broke and AMC wants you to save gas.

HD

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Guest PilotKD
Airlines figured this out a long time ago, amazing it is taking the military so long to follow suit.

my .02

-j

It's taking the Air Force so long to figure out because the Air Force isn't a business, is not run like a business and probably never will be. It's been run with lots of short term goals by people looking to piss on the proverbial tree and move on to bigger and better things with no conservation in mind. What happens at the end of every fiscal year? Units blow their money on stupid things they don't need so they don't lose the money. That's how we have so many plasma TV's hanging on walls to watch CNN.

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I totally agree with you J, but I don't think planners should tell pilots what amount of fuel they need without the pilot first justifying the needed fuel amount for their mission. The planner should then examining it closely with what they expect (what the planner had plan) and then reconciling it to account for variable(s) not previously considered and the like. I believe this system will be much more efficient. Furthermore, unlike the Airlines and FedEx that flies the same known routes, the military mission is quite different and diverse, and trying to make the AF fuel efficient should consider these variables that aren't present in civilian flying.

Just my two cent as a GA pilot with no military flying experience.

In the C-17 these planners have done a good job. They will not make a crew take off with less than needed for the mission. In fact this fuel planning process applies primarily to the "standard" routes that we fly. If you are doing something non-standard there is a good chance you'll do the fuel planning yourself. I don't like it when people try to tell me how to fly my jet but here are some facts.

The AF uses the most fuel in DoD.

AMC uses the most fuel in the AF.

C-17s use the most fuel in AMC.

That makes it difficult for us Heavy pilots to justify throwing on an extra 10k for the family or flying "morale speed"

So if your a C-17 pilot and you land with an UNID extra of 5k (extra gas) and meet all other requirements I've found that if I want to increase that UNID an extra 10k to 15k UNID extra it could cause us to burn an extra 5k of gas.

One sortie at 5000 pounds wasted. Lets say our gas weighs 6lbs a gallon thats 833 gallons at roughly 2 bucks a gallon. It costs the government 1600 dollars, multiply that by the hundreds of sorties flown each year in the C-17 and you can see why people care.

For C-17 guys out there be aware that if you divert, as soon as you do TACC will be looking at your flight history through AOC. They will know if you didn't fly the optimum altitude and they will know what your mach number is and they will know your fuel burn. I don't agree with all the measures taken, but ACs be prepared to justify why you weren't flying the optimum profile.

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For C-17 guys out there be aware that if you divert, as soon as you do TACC will be looking at your flight history through AOC. They will know if you didn't fly the optimum altitude and they will know what your mach number is and they will know your fuel burn. I don't agree with all the measures taken, but ACs be prepared to justify why you weren't flying the optimum profile.

Thankfully they don't watchdog us like that. That sucks.

HD

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Howsabout finding an efficient method for detaching/attaching the C-130 externals? Oldheads at LRF were espousing how the drag of the two externals burns one external's load of gas, therefore only giving you one external's worth of fuel range. It's worthless drag when you're only posting a 3.something training sortie that could be all be burnt out of the internals.

I'm sure it's all about the "wing relieving" fuel, but you could sent a few back to the depot for that cost.

Edited by The_Ginger
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