DCS P-51D QUESTIONS

[OLD CROW]

On 9/1/2021 at 3:03 AM, scipio47 said:

I cant seem to find any good information on formation flying with bombers on escorts. Ive messed around with trying to get some speed control but im struggling with keeping stable with B-17s without shifting left and right heavily. Does anyone know of any good resources or tutorials? Im new to warbirds in DCS so any help is appreciated.

Due they were always full of fuel (it means heavy weighted most part of the mission) mustangs were not the best in terms of acceleration so the "little friends" flew always in altitudes over the bomber boxes and to keep their speed higher than the bombers and to avoid the overshooting the "heavies" they just fly zigzagging the formations below them. So once you reach your desired cruise altitude just set the RPM & manifold pressure in Max. RPM 2400 & Max. 35 Hg. Also this technique is good to keep a good Situational Awarness all time due you can check their 3-9 zone regularly checked also yours cause their rear gunners can shoot hostiles in your 3-9 zone. Keep always an eye on any red tracer shot from bombers: they give you a clue from the direction where boogies are.

 

At the beginning of the Mustang implementation as the "standard Heavies Escort Fighter" Fighter squadrons break their escorting duties just to enter in evoluting fights with german decoy squadrons to separate Escort fighters and clear the path to the squadrons with the main goal of downing bombers. Due that, Fighter squadrons received the main orders of mantaining the escorting duties all way to Germany and from Germany to Home bases and always break any evoluting fight that goes lower than Angels 18 (18,000 feets). 

[Chipwich]

I usually climb above the bomber formation, set max continuous power, 2700 RPM, 46", and zig zag over the formation.  Then go to combat power when bandits show up.  Make sure that you trim to center the ball to reduce drag and drop tanks if you have burned off the fuselage tank and near the target area.  Alternately, set your switches to pickle drop tanks in case the bad guys show.  You have plenty of fuel in the  main tanks for an extended fight and RTB to England.  If you haven't done it already, make sure to either map an axis to carburetor ram air, or edit a LUA per this thread ,  Otherwise you won't be able to set enough manifold pressure above critical altitude.

 

 

[flygav]

On 8/31/2021 at 8:03 PM, scipio47 said:

I cant seem to find any good information on formation flying with bombers on escorts. Ive messed around with trying to get some speed control but im struggling with keeping stable with B-17s without shifting left and right heavily. Does anyone know of any good resources or tutorials? Im new to warbirds in DCS so any help is appreciated.

Thanks!

Be sure you stay in trim, ram air open. Climb above the bombers and then slight dive, you should be really moving then (true air speed wont be on the speed meter at that alt, youll be going a lot faster then indecated (it complecated I cant explain it but see link below)
https://www.boldmethod.com/learn-to-fly/aerodynamics/why-true-airspeed-increases-with-altitude/#:~:text=How Much Does True Aispeed,depends on temperature and pressure.

 

[Rapierarch]

Why does P-51 have night vision googles? 

[Gui_Santos]

After the last update i have noticied the engine is more Hot, or less cooling... The OIL temperature in 250mph 30mp and 2500rpm is still climbing...

[razo+r]

1 minute ago, Gui_Santos said:

After the last update i have noticied the engine is more Hot, or less cooling... The OIL temperature in 250mph 30mp and 2500rpm is still climbing...

Cooler switch confirmed in Auto or Open position?

[Catseye]

6 hours ago, Gui_Santos said:

After the last update i have noticied the engine is more Hot, or less cooling... The OIL temperature in 250mph 30mp and 2500rpm is still climbing...

Yes, started after the fix to the cooling system. Doing a normal climb at 50 lb boost and 2700 rpm and 200 mph, it requires constant switching from auto to full open on the oil temp switch and sometimes on the water temp switch. I immediately go to full open on both when engaging or driving the engine hard. The Spit on the other hand, works just fine in auto in all conditions. I still think that the P-51 requires more work in this area.

[Gui_Santos]

On 4/14/2023 at 10:09 AM, razo+r said:

Cooler switch confirmed in Auto or Open position?

Yes, my operation is the same, AUTO for normal operations (2400rpm and <40lb boost). And when more power open the coolers.

On 4/14/2023 at 4:30 PM, Catseye said:

Yes, started after the fix to the cooling system. Doing a normal climb at 50 lb boost and 2700 rpm and 200 mph, it requires constant switching from auto to full open on the oil temp switch and sometimes on the water temp switch. I immediately go to full open on both when engaging or driving the engine hard. The Spit on the other hand, works just fine in auto in all conditions. I still think that the P-51 requires more work in this area.

Same to me, is overheating with standard operation (2400rpm <40lb), need speed over 250mph to cooling.

[Art-J]

@Catseyeand @Gui_Santos, that doesn't sound right at all. Have you guys left game flight model by mistake, or air filter and carb heat on?

I've just done a flight on Normandy map with weather set to hot summer (30 degrees at sea level), did startup, warmup, mag and prop check at 50 degrees, took off, did one climb all the way up to 20 000 ft at max continuous power settings (46", 2700 RPM, 170 mph), then dove down to sea level and repeated it again with higher power settings (50", 2700 RPM, 170 mph). Not even once did I have to touch radiator switches - kept them in auto all the time and there was just no risk of overheating the engine - coolant never went above the redline, while the oil never went above 87-88 degrees. That's on latest Open Beta.

You know you don't HAVE to keep the oil temp in green range, right? Max limit in second half of the war was 90 (as seen on early type of temp gauge we've got modelled), got increased closer to the war's end to 105 (with relevant temp gauge replacement), but we don't even know which one is simulated in DCS after recent changes right now.

Edited April 20, 2023 by Art-J

[Catseye]

5 hours ago, Art-J said:

@Catseyeand @Gui_Santos, that doesn't sound right at all. Have you guys left game flight model by mistake, or air filter and carb heat on?

I've just done a flight on Normandy map with weather set to hot summer (30 degrees at sea level), did startup, warmup, mag and prop check at 50 degrees, took off, did one climb all the way up to 20 000 ft at max continuous power settings (46", 2700 RPM, 170 mph), then dove down to sea level and repeated it again with higher power settings (50", 2700 RPM, 170 mph). Not even once did I have to touch radiator switches - kept them in auto all the time and there was just no risk of overheating the engine - coolant never went above the redline, while the oil never went above 87-88 degrees. That's on latest Open Beta.

You know you don't HAVE to keep the oil temp in green range, right? Max limit in second half of the war was 90 (as seen on early type of temp gauge we've got modelled), got increased closer to the war's end to 105 (with relevant temp gauge replacement), but we don't even know which one is simulated in DCS after recent changes right now.

 

Hi ART-J,

This is encouraging and needs some testing. 

For some background, I am an experienced DCS Warbirds flyer. I always warm up the engine to specs prior to take off and maintain optimum specs whenever I fly. Air filters and carb heat are not on.

What I see here is your comment about max settings on the instruments. Both oil and water can move into the red zone on my climbs and that's when I open the rads. Perhaps this is where perception of allowable tolerances are in play. I often have coolant sitting up on the red line but the oil temp is often at "max" prior to water temps maxing out.  If you say they don't need to be always in the green, then I will do some tests in auto all the time and see what happens. I have never had an engine failure but assumed that it was essential to keep temps in the green therefore continually opening the rads. The Spit, on the other hand, always seems to stay consistent in auto regardless of the situation.

So, if the gauges are correct and my application of rad settings is misguided or . . . . . the gauges are a bit "sensitive" within hard conditions requiring tweaking, I need to come to grips with what is happening.

Thanks for your feedback,

Cheers,

Cats . . . 

Edited April 21, 2023 by Catseye

[Art-J]

There was a thread a few months ago with guys reporting maxing out the oil temp gauge during ground tests without any consequences, Nineline chimed in, it was supposed to be looked at. It was difficult to say it that was a bug or a feature with a 105 limit introduced (but our gauge just doesn't go that far). Then the cooling system changes rolled in in later game patches and nobody really knows how hot we can run now and for how long.

So, yeah, some extra testing might come in handy. That being said, green range seems to be used pretty much for cruise flight while you should be fine going up to 90 in more power-demanding scenarios.

[Gui_Santos]

16 hours ago, Art-J said:

@Olho de gatoe@Gui_Santos, isso não soa nada bem. Vocês deixaram o modelo de vôo do jogo por engano, ou o filtro de ar e o aquecimento do carburador ligados?

Acabei de fazer um voo no mapa da Normandia com o clima definido para verão quente (30 graus ao nível do mar), inicializei, aqueci, verifiquei a mag e a hélice a 50 graus, decolei, fiz uma subida até 20.000 pés nas configurações de potência máxima contínua (46", 2.700 RPM, 170 mph), depois mergulhou até o nível do mar e repetiu novamente com configurações de potência mais altas (50", 2.700 RPM, 170 mph). Nem uma vez precisei tocar nos interruptores do radiador - mantive-os no modo automático o tempo todo e simplesmente não havia risco de superaquecer o motor - o líquido de arrefecimento nunca ultrapassou a linha vermelha, enquanto o óleo nunca ultrapassou 87-88 graus. Isso está no último Open Beta.

Você sabe que não PRECISA manter a temperatura do óleo na faixa verde, certo? O limite máximo na segunda metade da guerra foi de 90 (como visto no tipo inicial de medidor de temperatura que modelamos), aumentou próximo ao final da guerra para 105 (com a substituição relevante do medidor de temperatura), mas nem sabemos qual é simulado no DCS após mudanças recentes agora.

 

I believe that the automatic function of the radiators never worked on the P51, just observe in the external view that it doesn't matter the temperature of the marker, they never move when the selector is in AUTO...

[Art-J]

That's not true, but keep in mind they'll start moving only when temps get close to the redline and/or when the airflow becomes insufficient.

Screenshots below show what happened after I warmed up the engine at 2300 RPM to 110 for coolant and 85 for oil (flaps did partially open already) and then cut the throttle, reducing the airflow to minimum. Both flaps immediately opened full.

 

 

[grafspee]

On 4/21/2023 at 2:50 PM, Gui_Santos said:

I believe that the automatic function of the radiators never worked on the P51, just observe in the external view that it doesn't matter the temperature of the marker, they never move when the selector is in AUTO...

Then you had to fly P-51 at extremes low power.

According to maintenance manual  opening and closing temperatures For Coolant and oil radiator shutter are as follows.

Coolant: opening temp 115c-118C, closing 102C-105C

Oil: opening 85C-87C, closing 71C-73C

You won't see coolant radiator shutters being open until coolant temp reaches at least 115C-118C and oil radiator shutter open until oil reaches at least 85C-87C

Since ED introduced new/upgraded cooling system in warbirds i fly P-51 100% time in auto exactly the same as every P-51's manual say to do.

 

I just did some testing, my conclusion is that oil/radiator shutter doors in Auto works exactly as per manual. I can clearly see that shutters won't open until opening temp is reached and once they open they stays open until closing temp is reached. This thermostat hysteresis may lead to different coolant and oil temps at exact same condition, it is very noticeable with oil temp, it is quite hard to reach oil temp 85C-87C but if you push enough power oil radiator shutter will open and then when you reduce power oil radiator shutter won't close until low 71C which is also quite hard to cool oil that much so depending what you've done before you may fly with closed or a little bit open oil radiator shutter with oil temp high like 84C or low oil temp like 74C at exact same speed and power.

Only explanation that on your end shutters seem not working is that you have them in manual mode not in Auto mode.

 

Edited April 23, 2023 by grafspee

[Gui_Santos]

On 23/04/2023 at 04:37, grafspee said:

Então você tinha que voar o P-51 em extremos de baixa potência.

De acordo com o manual de manutenção, as temperaturas de abertura e fechamento do obturador do radiador de óleo e refrigerante são as seguintes.

Refrigerante: temperatura de abertura 115c-118C, fechamento 102C-105C

Óleo: abrindo 85C-87C, fechando 71C-73C

Você não verá as persianas do radiador de refrigeração sendo abertas até que a temperatura do líquido de refrigeração atinja pelo menos 115C-118C e a persiana do radiador de óleo aberta até que o óleo atinja pelo menos 85C-87C

Desde que a ED introduziu um sistema de resfriamento novo/atualizado em warbirds, eu voo o P-51 100% do tempo no modo automático exatamente da mesma forma que todos os manuais do P-51 dizem para fazer.

 

Acabei de fazer alguns testes, minha conclusão é que as portas do obturador do óleo / radiador no Auto funcionam exatamente como no manual. Posso ver claramente que as persianas não abrem até que a temperatura de abertura seja atingida e, uma vez abertas, elas permanecem abertas até que a temperatura de fechamento seja atingida. Esta histerese do termostato pode levar a diferentes temperaturas do líquido refrigerante e do óleo exatamente na mesma condição, é muito perceptível com a temperatura do óleo, é muito difícil atingir a temperatura do óleo 85C-87C, mas se você pressionar o suficiente, o obturador do radiador de óleo abrirá e, quando você reduza a potência do obturador do radiador de óleo não fecha até 71 °C, o que também é muito difícil de resfriar o óleo, dependendo do que você fez antes, você pode voar com o obturador do radiador de óleo fechado ou um pouco aberto com a temperatura do óleo alta como 84 °C ou baixa temperatura do óleo como 74C exatamente na mesma velocidade e potência.

A única explicação de que as persianas parecem não funcionar é que você as tem no modo manual e não no modo automático.

 

 

Thanks friend, i will make a flight test with this informations and parameters for observe.

On 21/04/2023 at 12:32, Art-J said:

Isso não é verdade, mas lembre-se de que eles começarão a se mover apenas quando a temperatura chegar perto da linha vermelha e/ou quando o fluxo de ar se tornar insuficiente.

As capturas de tela abaixo mostram o que aconteceu depois que esquentei o motor a 2300 RPM para 110 para refrigerante e 85 para óleo (os flaps já estavam parcialmente abertos) e depois cortei o acelerador, reduzindo o fluxo de ar ao mínimo. Ambas as abas imediatamente se abriram completamente.

 

 

Thanks friend, i will make a test.

[eifionglyn]

This may or may not be a stupid question so I figure it goes here.

I have the VKB T-rudder pedals  - no toe brakes. I figure I can use the twist grip on my stick for differential braking. However, DCS picks up the twist as a single axis. If I assign it to the left brake and then assign it to the right brake it takes the assignment away from the left brake.

Is there a way for me to tell DCS to use the Z axis of the stick from centre to fully left as the input for the left brake and from centre to full right as the input for the right brake? 

Or alternatively, can I set a modifier somehow that when I hold a button down it makes DCS treat my rudder pedals as toe brake input?

Currently, I just use a hat on my throttle as toe brakes. It works, kinda, but it's not great.

[tacts.zeagle]

yes. But only if you map that axis as buttons.

You have to go into your Virpil Configuration Software and bring up the stick.

Then double click the axis you want to map and select 0, and 100% if you just want two buttons, then go to the BUTTONS tab and on the far right map the buttons. It's that simple.

I had to do this for my F-16 TMS on the Virpil Constellation Alpha stick. I just used a different axis than you. But the process is the same. 

Then go into DCS and set one of those newly mapped buttons to wheel brake left and one to wheel brake right.

[eifionglyn]

1 hour ago, tacts.zeagle said:

 

You have to go into your Virpil Configuration Software and bring up the stick.

 

Will Virpil's software talk to my VKB stick?

[tacts.zeagle]

I dont think so. I must have mis-read your post. I thought you had a virpil. My coffee meter was on the low side I guess.

[Mobile_BBQ]

I recently bought the P-51D. I took it up to 20,000+ feet and noticed that the Carb. Temp heat dropped down to -40 degrees and was definitely not in the +40 range "green zone" on the dial.  Is this normal?  I was running 46", 2700rpm the whole time.  The manual and in-pit placards indicate to not use Carb. Heat above 12,000 feet.  Are there any other methods to use to get the carb. temp back into the nominal range?  I couldn't find any further documents or tutorial videos to answer my question.

 

[saburo_cz]

It is normal and it is OK.

Green zone does not mean nominal range.

[Ala13_ManOWar]

On 10/8/2023 at 7:57 PM, Mobile_BBQ said:

I recently bought the P-51D. I took it up to 20,000+ feet and noticed that the Carb. Temp heat dropped down to -40 degrees and was definitely not in the +40 range "green zone" on the dial.  Is this normal?  I was running 46", 2700rpm the whole time.  The manual and in-pit placards indicate to not use Carb. Heat above 12,000 feet.  Are there any other methods to use to get the carb. temp back into the nominal range?  I couldn't find any further documents or tutorial videos to answer my question.

 

Usually way that up high there's not enough humidity for carb to create ice, so it's fine and normal as Saburo said. It'd be really bad at lower altitudes with visible, or even not visible, higher humidity and there is where one should use carburettor heat.

[=475FG= Dawger]

On 10/8/2023 at 12:57 PM, Mobile_BBQ said:

I recently bought the P-51D. I took it up to 20,000+ feet and noticed that the Carb. Temp heat dropped down to -40 degrees and was definitely not in the +40 range "green zone" on the dial.  Is this normal?  I was running 46", 2700rpm the whole time.  The manual and in-pit placards indicate to not use Carb. Heat above 12,000 feet.  Are there any other methods to use to get the carb. temp back into the nominal range?  I couldn't find any further documents or tutorial videos to answer my question.

 

Carburetor ice doesn’t happen when its cold outside. Ice forms when humid air rapidly cools as it entered the Venturi throat of the carburetor. The prime conditions are above freezing. The chart only goes down to minus 5. 

[Art-J]

And since carb icing and FOD are not simulated in DCS warbirds anyway, I'd recommend not fiddling with carb heat and air filter levers, especially when power loss caused by using one of them (don't remember which ATM) at high altitudes IS simulated. Just keep both forward and fly the plane (unless you want to use them strictly for immersion purposes).

[=475FG= Dawger]

7 hours ago, Art-J said:

And since carb icing and FOD are not simulated in DCS warbirds anyway, I'd recommend not fiddling with carb heat and air filter levers, especially when power loss caused by using one of them (don't remember which ATM) at high altitudes IS simulated. Just keep both forward and fly the plane (unless you want to use them strictly for immersion purposes).

Carb heat causes power loss. Hot air is less dense.