Fuel calculations

[Rhinozherous]

So, first time lost both engines due to dry tanks :-P Was not aware enough of my fuel levels... This brings me to fuel calc in the cat.

 

What is your source of Performance data for our tomcat? How do you guys do this?

[Possum]

Fuel mgmt is different off the boat than it is off the beach. With a beach landing option, you’ll set a joker/bingo based on distance to your point of landing. I’m sure there charts out there somewhere that will help set a profile and numbers.

 

When flying off the boat, fuel management is done by constructing a fuel ladder based on recovery time and max trap fuel weight. I’m not sure if that has been discussed here yet.

[Rhinozherous]

Unfortunately there is no Performance part in the Natops manual... Couldnt find it via google either.

 

How is Heatblur doing the calcs for programming it? Any source for us?

[Victory205]

Fuel mgmt is different off the boat than it is off the beach. With a beach landing option, you’ll set a joker/bingo based on distance to your point of landing. I’m sure there charts out there somewhere that will help set a profile and numbers.

 

When flying off the boat, fuel management is done by constructing a fuel ladder based on recovery time and max trap fuel weight. I’m not sure if that has been discussed here yet.

 

I'll add that to the landing tips paper. Sort of took it for granted, but setting up fuel reserves to make a time is a foreign concept to the average land lubber pilot...

 

Unfortunately there is no Performance part in the Natops manual... Couldnt find it via google either.

 

How is Heatblur doing the calcs for programming it? Any source for us?

 

Make your own. I never trusted the performance charts anyway until the data was verified personally.

 

Carefully set up your profile in the sim, note the fuel state on the totalizer, hack the clock and see the fuel burn over say, fifteen minutes to a half hour. Use the totalizer burn to calculate fuel burn per hour for your power setting, configuration, altitude and Mach/Airspeed. Record the TAS as well.

Edited March 23, 2019 by Victory205

[Rhinozherous]

I think I will trie and do testflights with writing down the numbers.

[Eldur]

You've got fuel flow gauges as well, unless you're trying to cruise with afterburners lit like I tend to do at high altitudes (like 48-54kft). I can go ~ M .85ish at 37kft with both engines rougly running at 3.2 on those gauges (pretty comparable to the Hornet BTW) with a clean airframe. That's 6400lbs per hour. Basically just look at your FF, double the indicated value and multiply by 1000 to get your total FF per hour if you stay there.

 

If you don't want to calculate your fuel for bingo, just have a look at the totalizer once you reach your target area or you get into a fight. Substract that from what you took off with and you know what you need to have left at least for a safe return. Add some 1-2k or even more to that for a boat trap to get more comfortable.

[KiraTheCat]

Add some 1-2k or even more to that for a boat trap to get more comfortable.

 

 

You're comfortable with only 1-2 around the boat? I'm not 100% sure, but in landing configuration, I figure on around 800lbs total burn per pass. I'm probably rather off, but I don't like to do my first pass with anything under 2000lbs in the tanks.

[Possum]

IRL, you need to show on the ball at max trap fuel weight. If you show up with less, you attract attention you don’t want. Every carrier aviator knows his fuel state at all times, and where he is on his fuel ladder. Hanging out at max conserve trying to get a few pounds back before the recovery starts is something every tailhooker has experienced.

[flybull]

Hi Possum/Victory

 

Thanks for your great SME feedback here.

 

Got a question: Showing up on the ball at max trap wt, would deprive you every sortie of the extra training time that "land lubber" brethren would enjoy until they burn down to their lower required fuel states....is this compensated for by increased sorties/hours per annum for USN guys?

 

I understand that hours flown has varied through time, conflicts etc - but as far as comparable - do USN fighter guys get more flight time to practice boat stuff PLUS all the other stuff everybody else does or does the boat flying cannibalise other training?

 

Thanks again!

 

Dave

[Victory205]

Hi Possum/Victory

 

Thanks for your great SME feedback here.

 

Got a question: Showing up on the ball at max trap wt, would deprive you every sortie of the extra training time that "land lubber" brethren would enjoy until they burn down to their lower required fuel states....is this compensated for by increased sorties/hours per annum for USN guys?

 

I understand that hours flown has varied through time, conflicts etc - but as far as comparable - do USN fighter guys get more flight time to practice boat stuff PLUS all the other stuff everybody else does or does the boat flying cannibalise other training?

 

Thanks again!

 

Dave

 

Possum, being a cheapskate, doesn't have the sim yet. He needs to get it ASAP. Until he does, he's referencing real world vice DCS.

 

Yes, fuel is always a balance depending upon whether you have a bingo field in range, what the Airwing policy happens to be, and the mission. Ashore, once you had the gear down for the first pass, then you'd likely do touch and goes until you had a low fuel light. The point being that you didn't need to save fuel to troubleshoot a possible gear issue once you were fully configured.

 

As stated before, we left the gear and flaps down between landings (unless diverting, etc).

 

We flew a lot more than USAF (and way, way more than our adversaries) did when I was on active duty. I don't know what's going on now, but some of the USAF numbers I hear from recently separated Zoomies are appallingly low. I see why they are unhappy.

 

Possum is about two decades younger than I, so he can bring you up to speed on what came later, but it is probably true that USN spent a lot of OPTAR doing landings. In my day, we still probably flew more tactics than USAF.

 

The French Navy pilots by the way, all flew exactly the same number of hours, with only LCDR (equivalents) allowed to land on the ship at night. They got more hours than the daytime only Junior Officers. We in contrast, were always fighting for more time. Some of the married guys wanted to go home at night, while we bachelors snarfed their flying. ;)

[Rhinozherous]

I did two testflights, one with 100% RPM and one with 90% RPM in different altitudes. See attachment for the sheet.

 

The numbers are just written down via looking at the gauges and I am aware that they are in no way accurate. But I will trie and see and make it more exact over time.

 

See sheet for conditions for the flights.

Maybe it is helpful for other, feel free to use the sheet for whatever you want.

[Possum]

I did two testflights, one with 100% RPM and one with 90% RPM in different altitudes. See attachment for the sheet.

 

The numbers are just written down via looking at the gauges and I am aware that they are in no way accurate. But I will trie and see and make it more exact over time.

 

See sheet for conditions for the flights.

Maybe it is helpful for other, feel free to use the sheet for whatever you want.

 

Here is a bingo profile for the A model I found on Google, the profile will be similar for a B. Try a similar profile to get a baseline fuel burn.

[VampireNZ]

The thing with 'simulators' is they are usually based of the performance of an actual airframe for certification purposes. As I doubt that DCS uses the same philosophy as actual Level-D sims - I can't see why the performance of the F-14 in DCS would vary at all from perfect -1 performance figures in all aspects.

 

IRL, as Victory said, you take the perf figures quoted in books with a grain of salt as every turbine engine has it's own story to tell and could either be way better or way worse performing than the 'optimum' figures in performance graphs (up to the limits of performance to keep it installed - too bad and it gets swapped out). Same with the drag index of the frame.

[Nascar]

How do you manage the external tanks in the F-14? Can you drain them first?

Edited March 25, 2019 by Nascar