Throttle issue

[GGTharos]

On 2/8/2023 at 1:08 PM, Gilligan said:

Okay, I turned on the loud after burner sounds in the audio menu, and that definitely helps make it more obvious when the AB has kicked in. I will keep AoA in mind when at higher altitudes or lower speeds or just in general. I haven't been paying much attention to that except when the water line is a whole-ass 5+ degrees above the path indicator. 

Select the number of fuel tanks you want:

Center tank and the two wing tanks have nearly equal drag.   So 2W + 1C = 2x Drag.

As a rule of thumb, take 3 tanks if you need to loiter for a long time - that means tooling around at the highest altitude where you can maintain 250kts in a 30 deg bank, conserving fuel.  Drag increases with speed, so that's how you manage that.

If you're not going to loiter, choose 1 or 2 tanks, depending on desired gross weight.  As said above, either configuration has the same drag.

 

Typical take-off procedures look like this:

AB to 250kts (AB used on T/O for safety reasons) then MIL, pitch for 300kts (meaning leave the throttle in mil, accelerate to 300kts then use pitch only to maintain 300, then 0.9M at the cross over altitude (you'll find at some point 300kts = 0.9 mach, at this point you maintain 0.9 mach).  Do not attempt to maintain a steady climb angle, pitch for speed as required, that means you'll be decreasing pitch as you climb.

An AB climb is similar but you pitch for 350kts and cross over to maintain 0.95 mach.  Yes, you have to be precise.

These are just two profiles, not THE profiles, they give you economy and good climb vs. fuel/distance from airfield to altitude metrics.  If you need to get to altitude faster, remain in AB all the way, accelerate to 500kts on the deck and then pitch for a 450kt climb initially.

Select your cruising altitude according to how far you have to fly.  Short hops don't require that much altitude.

Ignoring flat dash intercepts (which are high mach sprints), at cuising altitude set a cruising SPEED.   That's say 300kts.   Once you're likely to enter a fight accelerate to 400kts or 0.95 mach, or faster if you need more energy.

 

Regarding your engine settings, learn to monitor all gauges:

• RPM will be 96 at MIL and above.
• FTITs will be at 970 at MIL and above.
• Your engine nozzle gauges remain at minimum opening on mil and then open more with each stage of AB (that's how you tell, not sound, but that works too)
• Your fuel flow engines - cross-check with your fuel total to figure out how long you can stay in the air.  This is your basic pilot math for flying.
• On your fuel gauge, make sure to set joker/bingo (there's only one indicator/control for this so once you hit joker, reset it lower for your bingo)

You can check the manual to see where all these gauges are.

Conserving fuel in a fight is directly affected by how fast you kill your bandits, so ... make sure they go down quickly.

Finally, all of this is tip of the iceberg type stuff.

On 2/8/2023 at 1:08 PM, Gilligan said:

I'm pretty okay with the concept of thinner air at higher altitudes, and how that translates to less fuel burn, faster AMRAAMs, etc. Cruising I'm fine with, I can conserve fuel while traveling, but once the fight is on it seems to run out almost immediately. I need to work on the fast climb though. For now I've been keeping it about 7.5* to keep from losing to much airspeed while climbing - usually with some degree of AB engaged. 

Thank you. I've been through the f15c tutorials provided for by the Grim Reapers youtube channel (among others), but I will go through this set as well. 

 

[Nahen]

I don't know if it's the resistance of the three tanks or the two tanks - but rather their weight, anyway, maintaining speed with three tanks and with two are two different things. That's why I avoid flying with three tanks. At altitudes above 35,000 feet, it is virtually impossible to fly without a afterburner, the speed drops to the limit stall very quickly. The only option is the afterburner - accelerate to 300-350 knots, turn off the afterburner and turn it on again in a moment and accelerate ... and so go around...
 With two you can safely fly and keep those 200-250 knots at high altitude.

[draconus]

20 hours ago, Nahen said:

I don't know if it's the resistance of the three tanks or the two tanks - but rather their weight...

It's both.

[Pavlin_33]

On 2/10/2023 at 7:29 PM, Nahen said:

I don't know if it's the resistance of the three tanks or the two tanks - but rather their weight, anyway, maintaining speed with three tanks and with two are two different things. That's why I avoid flying with three tanks. At altitudes above 35,000 feet, it is virtually impossible to fly without a afterburner, the speed drops to the limit stall very quickly. The only option is the afterburner - accelerate to 300-350 knots, turn off the afterburner and turn it on again in a moment and accelerate ... and so go around...
 With two you can safely fly and keep those 200-250 knots at high altitude.

At 35.000 feet you should be looking at the Mach number instead of K-nots.

[Nahen]

15 hours ago, Pavlin_33 said:

At 35.000 feet you should be looking at the Mach number instead of K-nots.

Irrelevant. At 35,000, around 300 kts is around Mach 1. In an F-15 with three tanks, you won't be able to maintain that speed without afterburning. With two tanks, if you skillfully accelerate, Mach 1 can be maintained above 40,000 and without tanks at 35,000. At 40,000, Mach 2 is about 500 knots. In addition, the question of whether IAS or TAS 90% of "flyers" in DCS use knots regardless of the flight altitude, especially beginners. In the case of the F-15 module, it does not matter because you only have one type of speed given by the aircraft's avionics, so there is no risk of "discrepancy"

[Pavlin_33]

3 hours ago, Nahen said:

Irrelevant. At 35,000, around 300 kts is around Mach 1. In an F-15 with three tanks, you won't be able to maintain that speed without afterburning. With two tanks, if you skillfully accelerate, Mach 1 can be maintained above 40,000 and without tanks at 35,000. At 40,000, Mach 2 is about 500 knots. In addition, the question of whether IAS or TAS 90% of "flyers" in DCS use knots regardless of the flight altitude, especially beginners. In the case of the F-15 module, it does not matter because you only have one type of speed given by the aircraft's avionics, so there is no risk of "discrepancy"

I should have written "at high altitudes" or "above a certain" altitude. My intent was not to refernce that particular altitude of 35k '.

[Nahen]

4 hours ago, Pavlin_33 said:

I should have written "at high altitudes" or "above a certain" altitude. My intent was not to refernce that particular altitude of 35k '.

Anyway, it's not important because the vast majority of DCS flyers - as I wrote, especially beginners - use knots.

[Pavlin_33]

27 minutes ago, Nahen said:

Anyway, it's not important because the vast majority of DCS flyers - as I wrote, especially beginners - use knots.

Well, the whole point is that it is and they should

[Nahen]

14 hours ago, Pavlin_33 said:

Well, the whole point is that it is and they should

You know, for example, on the public servers of the community of which I am a member, it is supposedly obligatory to use SRS ... And how is it in reality during take-offs, landings, etc.? It's the same with speed in Mach

[Gilligan]

On 2/9/2023 at 11:08 PM, GGTharos said:

Select the number of fuel tanks you want:

Center tank and the two wing tanks have nearly equal drag.   So 2W + 1C = 2x Drag.

As a rule of thumb, take 3 tanks if you need to loiter for a long time - that means tooling around at the highest altitude where you can maintain 250kts in a 30 deg bank, conserving fuel.  Drag increases with speed, so that's how you manage that.

If you're not going to loiter, choose 1 or 2 tanks, depending on desired gross weight.  As said above, either configuration has the same drag.

 

Typical take-off procedures look like this:

AB to 250kts (AB used on T/O for safety reasons) then MIL, pitch for 300kts (meaning leave the throttle in mil, accelerate to 300kts then use pitch only to maintain 300, then 0.9M at the cross over altitude (you'll find at some point 300kts = 0.9 mach, at this point you maintain 0.9 mach).  Do not attempt to maintain a steady climb angle, pitch for speed as required, that means you'll be decreasing pitch as you climb.

An AB climb is similar but you pitch for 350kts and cross over to maintain 0.95 mach.  Yes, you have to be precise.

These are just two profiles, not THE profiles, they give you economy and good climb vs. fuel/distance from airfield to altitude metrics.  If you need to get to altitude faster, remain in AB all the way, accelerate to 500kts on the deck and then pitch for a 450kt climb initially.

Select your cruising altitude according to how far you have to fly.  Short hops don't require that much altitude.

Ignoring flat dash intercepts (which are high mach sprints), at cuising altitude set a cruising SPEED.   That's say 300kts.   Once you're likely to enter a fight accelerate to 400kts or 0.95 mach, or faster if you need more energy.

 

Regarding your engine settings, learn to monitor all gauges:

• RPM will be 96 at MIL and above.
• FTITs will be at 970 at MIL and above.
• Your engine nozzle gauges remain at minimum opening on mil and then open more with each stage of AB (that's how you tell, not sound, but that works too)
• Your fuel flow engines - cross-check with your fuel total to figure out how long you can stay in the air.  This is your basic pilot math for flying.
• On your fuel gauge, make sure to set joker/bingo (there's only one indicator/control for this so once you hit joker, reset it lower for your bingo)

You can check the manual to see where all these gauges are.

Conserving fuel in a fight is directly affected by how fast you kill your bandits, so ... make sure they go down quickly.

Finally, all of this is tip of the iceberg type stuff.

 

First off thank you for the info and write up. I know it takes time to do so thank you for taking it to help me out.

I'm trying to take all your tips to heart and be conscious of them while playing.

I'm working my way through the f15c bear trap campaign and just finished up mission 6. This was a really long flight so I used all I've learned in here to conserve fuel to reach the target & etc.

 

To debreif, Took of from vaizani* or however it's spelt, target waypoint was at Nal'Chik or something like that, about a 20 minute flight from take off. I took 2 tanks. AB for takeoff with flaps down, cut ab at 250knts and start pitching up to about 7-10* around 275-300knts. I'm not as precise as I think I need to be yet but this has been working. I stay down till around 500knts and start climbing. I'm not doing great at keeping the speed constant-ish but I am getting better. I climb to around 35k feet and cruise there at 350knts as this is mission parameters for timing the SEAD strikes correctly. I'm not great at maintaining it without AB but, keeping an eye on the nozzle gauge has helped me keep AB use at a minimum. 

 

 

Tanks were empty at the target waypoint basically, dropped them and started engaging enemy CAP aircraft. 4 kills, 2 bug outs, but I was basically out of gas by the end of the fight, which I feel like went fairly quickly. I was on E before I made it back to the mountains, and had to eject over hostile territory. I'm not sure what I could have done differently to ensure a safe RTB.

 

 

I did a little measuring in google earth and it's only about 150 miles from Vaizani to Nalchik IRL. I feel like that's not a massive distance. I can drive further than that on a tank of gas. So I think I must still be doing something wrong to have been out of fuel like I was. 

Edited February 14, 2023 by Gilligan

[GGTharos]

Turn off AB.  150nm at AB is like flying 700nm.   This includes any time you spend climbing.  Basically AB burns about 3-5 times more fuel, and that's 2x more still at low altitude.

 

If you cannot maintain 350kts at 35000', drop to 25000'.

Edited February 14, 2023 by GGTharos

[Ironhand]

On 2/14/2023 at 11:14 AM, Gilligan said:

To debreif, Took of from vaizani* or however it's spelt, target waypoint was at Nal'Chik or something like that, about a 20 minute flight from take off. I took 2 tanks. AB for takeoff with flaps down, cut ab at 250knts and start pitching up to about 7-10* around 275-300knts. I'm not as precise as I think I need to be yet but this has been working. I stay down till around 500knts and start climbing. I'm not doing great at keeping the speed constant-ish but I am getting better. I climb to around 35k feet and cruise there at 350knts as this is mission parameters for timing the SEAD strikes correctly. I'm not great at maintaining it without AB but, keeping an eye on the nozzle gauge has helped me keep AB use at a minimum. 

 

 

Tanks were empty at the target waypoint basically, dropped them and started engaging enemy CAP aircraft. 4 kills, 2 bug outs, but I was basically out of gas by the end of the fight, which I feel like went fairly quickly. I was on E before I made it back to the mountains, and had to eject over hostile territory. I'm not sure what I could have done differently to ensure a safe RTB.

I'm hardly ever in the F-15C's pit so I don't know the aircraft well. But it seems strange that your wing tanks are empty by the time you get to Nalchik. I don't know the mission you're flying but, taking off from Vaziani with 2 wing tanks and 8 AAMs, I reached 35,000 ft 49 nm from Nalchik at roughly M0.9. Arrived over Nalchik with 4500 lbs of fuel remaining in the wing tanks (17,900 lbs total). I flew the profile in the thread I linked to earlier.

I've attached the TRK file, if you feel like getting bored watching it. This is not a combat mission. Just flew the profile I had linked to. Climb at 350 until M0.9 is reached and M0.9 thereafter.

F-15C MIL Power Flight--Vaziani to Nalchik.trk

Edited February 15, 2023 by Ironhand
correct my math, I hope

[Gilligan]

I tried the next mission in the campaign which calls for a similar flight from Vaizani to Mozdok (Beslan). I took 2 tanks again and was able to do a much better job controlling my speed up to my cruising altitude, and maintaining it from there. I made it to the bullseye with a decent amount of fuel in the bags. definitely not 4500 tho. Don't they start with a couple hundred more than that?

I eventually had to Jettison them in combat and was shot down by an SAM before starting the return leg. I'm not sure how much fuel I Had left at that point. 

[Ironhand]

22 minutes ago, Gilligan said:

…definitely not 4500 tho. Don't they start with a couple hundred more than that?…

Glad you’ve finally gotten a handle on it.

2 bags adds 8200 to the internal load of 13,400. So in my flight I still had the equivalent of a full bag plus a little arriving a Nalchik.

[Gilligan]

I wouldn't say a full handle but I'm getting more of it I think.

Although today I am having trouble completing missions that were a breeze before after I accidentally restarted my bear trap campaign. 

RedFor's Fox-3's are giving me trouble where I did not feel that threatened by them before. I don't know if this is because I am just lower energy when the fight starts or if I'm doing something different. But that's a problem for another thread I suppose. 

[Ironhand]

6 hours ago, Gilligan said:

…RedFor's Fox-3's are giving me trouble where I did not feel that threatened by them before. I don't know if this is because I am just lower energy when the fight starts or if I'm doing something different…

Can’t help you there. I’m more likely to be the one lobbing the R-77s at you.  But you should have the range advantage. So I really don’t know.

Edited February 20, 2023 by Ironhand

[Nahen]

Take three tanks, take off from Vaziani and fly to Anapa-Vitiazievo. If you reach this airfield, it means you can control the fuel

Edited February 19, 2023 by Nahen

[draconus]

On 2/19/2023 at 10:47 PM, Nahen said:

Take three tanks, take off from Vaziani and fly to Anapa-Vitiazievo. If you reach this airfield, it means you can control the fuel

That's 420nm. With 3 bags and 8AAM it took 9'000lbs of fuel so I shouldn't be even allowed to land that heavy.

[Gilligan]

On 2/19/2023 at 3:25 PM, Ironhand said:

Can’t help you there. I’m more likely to be the one lobbing the R-77s at you.  But you should have the range advantage. So I really don’t know.

 

Exactly. I *should* have the advantage. Haha. I pushed my engagement ranges out by another 5 to 10nm and that seems to have helped some I think. I wish I had more flight time available to really test things out but I don't think it's going to pan out for me in that regard any time soon. 

 

 

 

My biggest issue with managing flight range at the moment is that it's just so dang boring going that slowly, and takes for ever to get anywhere. But that's a "me " problem I think.

On 2/19/2023 at 3:47 PM, Nahen said:

Take three tanks, take off from Vaziani and fly to Anapa-Vitiazievo. If you reach this airfield, it means you can control the fuel

 

420 nm @ 250 knots = 1 hour 40 minutes and 48 seconds?

 

Pass. LOL

[Ironhand]

1 hour ago, Gilligan said:

420 nm @ 250 knots = 1 hour 40 minutes and 48 seconds?

 

Pass. LOL

No. More like 40-45 minutes, I think. You’re dealing with IAS and the higher you go, the more speed that number actually represents. Assuming you’re at 35,000 ft, that 250 knots (IAS) would translate to somewhere around 580 knots at sea level.

Edit: 250? I thought the climb was at 350 to M0.9 and M0.9 thereafter. Regardless, it’ll be less than 1:45.

Edited February 27, 2023 by Ironhand

[draconus]

16 hours ago, Gilligan said:

420 nm @ 250 knots = 1 hour 40 minutes and 48 seconds?

Already answered but for testing you can use time acceleration and do it in 20 minutes. Also with 3 bags you can do it almost entirely on full burners - so it was not really a good example of fuel management by Nahen.

Edited February 28, 2023 by draconus

[Ironhand]

5 hours ago, draconus said:

You mixed AB and non-AB profiles. Check this post:

No I didn’t. Both are climb at 350.

Quote

If at MIL power, climb at 350 knots to 0.90 Mach, then maintain 0.90 Mach

The difference is the Mach number at crossover.

[draconus]

13 minutes ago, Ironhand said:

No I didn’t. Both are climb at 350.

The difference is the Mach number at crossover.

You're right, sorry, have just checked again -1. What's your source @GGTharos?

Edited February 28, 2023 by draconus

[Ironhand]

5 minutes ago, draconus said:

You're right, sorry, have just checked again -1.

 No problem. I had double-checked myself before making the post to Gilligan. So much info to keep track of.

[GGTharos]

30 minutes ago, draconus said:

You're right, sorry, have just checked again -1. What's your source @GGTharos?

 

My -1 is my source.   Section 2-9.

300 to 0.9 at MIL,

350 to 0.95 at MAX.