Tom's Cat
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The only B variant Tomcat produced.
I’ve no able to build the prototype long-probe for it,also the PW-style exhaust as of what featured F-16,sorry!;-)
That’s interesting although not entirely correct. I’ll stop asking you what exactly you wanna tell us with your posts, as you’ve ignored my previous two attempts.
You can ask, comment, contribute, critique, make a joke, talk about F-14 related issues >here< (historical tidbits, FM or whatever as the number of interested people is too small to open a different thread for everything) BUT for your own work which I have nothing to do with please feel free to open your own thread. Otherwise it just confuses the hell out of everyone and, in addition, slightly annoys me.
Thank you.
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Yeah …
Cheers,
LSHahaha, nice that for yourself…
So and with my thanks, you have now 600.
Means, that I ROCK. :rofl:
Nikos. -
Lazystone man,
I spent last night creating countless rivet brushes and paths for all the panels. You have saved me probably 1000s of hours :D. Again many thanks for the valuable input! The Cat appreciates it as well…as you shall soon see
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So and with my thanks, you have now 600.
Means, that I ROCK. :rofl:
Cheers,
LS -
BTW.
Cheers,
LSHahaha, that was great fun mate…
And just think that i’m a civil engineer in real life, so i really RULE :rofl:
Nikos. -
Finally, after few weeks of “fasting”, i got some quality time with my BMS installation. I started the AFM tests again and today i managed to test the 1, 3, 5 and 6.5g entry and sustained mach points on the F-14A at 53-55000 lbs of gross weight at 0-1000ft altitude. Because of the test setting (at full AB) each test had to be run only for a short time (2-3 minutes). The 3, 5 and 6.5g sustained turns per mach were as far as i could compare with the available data and my stick discipline, spot on (within 0.1-0.2g). Next, i went to the on the deck dash and level flight envelope test, as well as the landing speed. The AFM turned out less precise here. The absolute dash consistently hit the wall at 1.08 and it should have gone to around 1.14 for the configuration flown. The stall speed is also too high. For the same load it should have been around 100-110 KIAS (0.145-0.16 mach region) and the in-sim the Turkey doesn’t fly below 0.2 mach (at least i could not find a value for AoA that i could sustain to keep it level). Somewhat better, but still a bit too high is the landing speed, or approach AoA (depends on which value you use when landing). At 10.5 degrees the speed is around 140KIAS and at 12 degrees it is around 128-130KIAS, while it should be 130KIAS at 10.5 degrees. Again, my stick discipline may be a bit off here. Still the difference is smaller then the min-max level flight issue. It would be nice if someone could replicate the tests.
The next time i have some free time, i’ll be off to angels 5 and 10 and see how the AFM fares there.
Happy flying guys! -
Just a short update on the tests, instead of going to angels 5 and 10, i stayed on sea level to test the CL max values. The AFM’s is more precise here as the mach increases again, and less precise as the mach drops, thus effecting the low speed nose pointing of the cat in the left most part of the envelope. Has the current AFM been moded to incorporate some safety measure? It seams there is no buffet onset so it is possible. All the values i got as you’ll soon see, stop at least 1/2g before the buffet could develop. This are the entry points i tested: mach 0.28, 0.38 and 0.46 that should give instantaneous pulls of 3, 5 and 6.5g. Instead i got 2.3, 4.5 and 6.1.
My impression is that the energy retaining and maintenance are better modded then the aerodynamic features. Maybe it’s the engine limitations? Only one thing remains to be tested and it’s the roll rates. Does anyone have any idea what those should be per mach value/wing sweep?
Happy flying and clear skies!P.S. While exporting the FM data i noticed the F-14A thrust per mach uses the data of 17000+pds per engine as static thrust on sea level. MATS lists this value as the static thrust value for the F-14A, but the same site rates the TF-30 engines at 20900pds of static thrust and pretty much every brochure i found on the net follows suit. At first i thought the engines were detuned to extend service life, but and 81-82% tune would be a bit excessive especially on a naval platform when every pound counts. Does anyone knows what should the static thrust be at sea level? Time to consult the flight manual i guess.
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Update 3
Over the weekend i finally had some free time on my hands. Not enough to measure acceleration and top speed, but quite enough to complete the 1, 3, 5 and 6.5g sustained and instantaneous pulls at 10 and 20k.
First the results on sustained g’s. As with the sea level test, both 10kft and 20kft results are very precise. Even with the lesser accuracy of my test (it’s more difficult to calculate how much fuel you need to start with in order to climb at angels 20 and still have enough for few minutes at test gross weights) the results are well withing 0.1-0.3 g’s of the desired values.The CLmax on the other hand was again less precise. The stall speed at 10 and 20kft were 0.4 and 0.3 true mach numbers above my reference data. The 3g pulls were off by 0.3 and 0.4g at the same mach respectively which leads me to the conclusion that medium altitude AoA performance is a bit more precise then low altitude AoA. At least the 3g pulls. The 5g and 6.5g were less precise. The first was 1 and 0.7g off the chart and the 6.5g, 1 and 1.3g off. And when i mean off, i mean less, as in the F-14 was unable to reach the desired load even for a fraction of a second for the given IAS/TMN.
Next on schedule, exit points for the sustained g loads, top speed per altitude and acceleration tests for different fuel loads.
My overall impression is that the high AoA behavior needs some rework (stall speed CLmax curve).
What do you guys think? Should i continue these tests up to angels 50? They will be less an less precise as the altitude increases. Unless someone figures out how to create a mission with the plane stating with a fraction of the mac fuel that is. Each time i set it to given value and altitude it resets to full tank at the start. The only way i found to start with custom fuel is to start on the ground/carrier. Does anyone have a solution for this? -
The only way i found to start with custom fuel is to start on the ground/carrier. Does anyone have a solution for this?
Hit a tanker? Or dump fuel.
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Does the Tomcat support air refueling in BMS?
Q2, as we don’t have a working pit for the F-14, i have no idea how much fuel i have at any given moment -
Don’t forget the TF-30 as installed in the F-14 develops 30000 lbs of thrust per engine at Mach 0.9 at sea level. I have no idea if the game engine can support varying thrust regimes for specific altitudes and airspeeds.
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Does the Tomcat support air refueling in BMS?
Q2, as we don’t have a working pit for the F-14, i have no idea how much fuel i have at any given momentyou can always substitute the f16 pit in the 14 to get fuel values.
i am very interested in your work here, one thing i also have noticed, is a high g turn, into a cloud (where the plane starts bouncing with turbulence) sometimes results in a depart from controlled flight, unable to recover…
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Don’t forget the TF-30 as installed in the F-14 develops 30000 lbs of thrust per engine at Mach 0.9 at sea level. I have no idea if the game engine can support varying thrust regimes for specific altitudes and airspeeds.
yes, the flight model takes altitude and airspeed into account for thrust values.
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Nice to read that some work on the FM is being done!
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Nice to read that some work on the FM is being done!
It’s mostly testing of the existing AFM at the moment, as i have no idea of how to modify the AFM file in a way that would make sense. The basic FM is much more simple to comprehend. I would welcome any help and hints on that subject. Tutorials, documentation, anything….
you can always substitute the f16 pit in the 14 to get fuel values.
i am very interested in your work here, one thing i also have noticed, is a high g turn, into a cloud (where the plane starts bouncing with turbulence) sometimes results in a depart from controlled flight, unable to recover…
That is a very good idea!
I have managed to induce a non recoverable departure too on few occasions, by pulling hard and yawing at the same time while flying in deep buffet. I was rather low though (if memory serves, bellow angels 10).Don’t forget the TF-30 as installed in the F-14 develops 30000 lbs of thrust per engine at Mach 0.9 at sea level. I have no idea if the game engine can support varying thrust regimes for specific altitudes and airspeeds.
That is why i was asking about the thrust. From dogfighting experience, i have come to notice that if you stay above mach 0.8 when entering energy eggs or other vertical maneuvers, the F-14A acts as an energy fighter (which is accurate). However depending on the static thrust values it can be underpowered or overpowered. In your example, the max thrust at mach 0.9 could be either 26+kpds or 30kpds per engine, or from 17kpds to 20+kpds static. 2.5-4kpds of thrust per engine can be quite a bit of margin for an AC that has a chronic lack of it. Have the engines ever been historically de-rated for some reason? Or has some of the thrust been lost because of intake geometry or something?
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It’s mostly testing of the existing AFM at the moment, as i have no idea of how to modify the AFM file in a way that would make sense. The basic FM is much more simple to comprehend. I would welcome any help and hints on that subject. Tutorials, documentation, anything….
That is a very good idea!
I have managed to induce a non recoverable departure too on few occasions, by pulling hard and yawing at the same time while flying in deep buffet. I was rather low though (if memory serves, bellow angels 10).That is why i was asking about the thrust. From dogfighting experience, i have come to notice that if you stay above mach 0.8 when entering energy eggs or other vertical maneuvers, the F-14A acts as an energy fighter (which is accurate). However depending on the static thrust values it can be underpowered or overpowered. In your example, the max thrust at mach 0.9 could be either 26+kpds or 30kpds per engine, or from 17kpds to 20+kpds static. 2.5-4kpds of thrust per engine can be quite a bit of margin for an AC that has a chronic lack of it. Have the engines ever been historically de-rated for some reason? Or has some of the thrust been lost because of intake geometry or something?
From what I understand the first TF-30s might have been detuned because a shortage of engines and the problems with catastrophic failure at that time. Later mechs from the 80s deny ever hearing of such a thing. Historically, Navy jets always have maximum thrust available for safety around the boat during cats/traps and aren’t defined like their Air Force brethren in peacetime to save engine life.
The TF-30 is a strange motor. High fuel economy down low, that insane thrust at mach .9, then the weakness pretty much everywhere else except very high and fast, where it edges past the F-110 again. Perhaps the F-111 determined where the emphasis was during the design phase of the TF-30, a high speed/ high endurance motor meant for intercepts or low level delivery of ordnance.
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If so, then i think the current AFM represents the early TF-30s (before strengthening of the blades). Would this affect the max dash speed at sea level i still don’t know though. The data i have for comparison seams to be for the 80’s version of the engines. However, the extra Ps curve in BMS follows closely the values i have which would indicate normal installed thrust. I will have to continue testing especially at higher altitude. Maybe it is just down low that the dash is off.
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Finally some free time on my hands today. Not enough to test acceleration values, but enough for dash speeds. First impression, the Cat as mentioned before seams slow. I flew in several directions just to make sure i was not running against the wind and this is what i got:
Alt 0-1kft mach 1.09 715knots (should be closer to 1.14)
Alt 5kft mach 1.14 710knots (should be around 1.25)
Alt 10kft mach 1.25 707knots (1.40)
Alt 15kft mach 1.29 683knots (1.50)
Alt 20kft mach 1.42 681knots (1.63-1.64)I was about to propose thrust boost, when i got the idea to actually test a clean F-14 on the deck……result:
Alt 0-1kft mach 1.23 814knots
very close to the 1.26-1.27 maximum dash at sea level. My conclusion, the F-14A is not so much underpowered as the stores cause way too much drag. I’m talking Sparrows and Winders here, no external fuel tanks. Propositions? -
Perhaps this connects to the centerline AIM-54 misalignment and there’s something in general wrong with the loadout effect on the FM. Cuz now we have a roll effect when the centerline hardpoints are used as well as a Moe than usual drag on outer pylons and the droptanks…
One question, you keep talking about the F-14 A. Do you only test the A model and is there a more than visual difference between the variants as far as the engine goes? Or do you just mention that cuz all variants are based on engine data of the F-14A anyway?
How about the fuel levels? Did you find a solution for that?
Lastly, the glove vanes. Do you know if they work and if so what their effect is in sim?
Thanks for all the catlove man!