Skewgear

Not sure they were fixed as much as temporarily worked around with Miss Shilling's Orifice. Here's the master of all things Merlin writing about carb development and operation at detail and length, complete with Merlin carb diagrams. https://www.calum-douglas.com/article-1-rolls-royce-merlin-carburettor-development/ What I take from that is our Mosquito should be susceptible to rich/negative G cut-outs under sustained -G, bearing in mind the fuel flow restrictor was not a complete cure for the problem. That only happened with the 60-series Merlins and their Bendix-Stromberg pressure carbs (which is why our Spitfire doesn't cut out under negative G). The other point of note is carb icing should definitely affect our Mosquito with its Merlin 24/25 engines and their SU AVT40 carbs, at least until the engine oil temp is up within minimum operating limits.

Welcome new players, especially Il-2 refugees. You may find our website page on SRS is helpful: https://projectoverlord.co.uk/how-to-use-srs-for-radio-comms-on-project-overlord/ As is our Mission Information page, which also contains the map MrExplosion posted above: https://projectoverlord.co.uk/mission-info/ And last but least, player statistics. Work is under way to enhance these. https://projectoverlord.co.uk/stats/ Oh, and the PO development blog for fellow history buffs. https://projectoverlord.co.uk/blog/ Enjoy!

Doesn't matter. A little aft stick is necessary to get airborne anyway. When you're actually taking off you're focused outside the cockpit, not gazing at the stick! When you raise the nose, the gyroscopic forces from the prop will induce a swing to the left. You need to anticipate and counter this with appropriate right rudder input at the same time as you bring the nose up. Not a boot full but a gentle press and hold, varying the pressure as required to keep tracking straight down the runway. Takes some practice to master it. Nah, that's what the trimmers are for. Don't forget to swap fuel tanks every 5-10 minutes and retrim as required, else you end up flying one wing low and wondering what's going on.

Not at the moment. There are limited opportunities to control static flak guns at some airfields but it's not really true Combined Arms. Right now we've slowed development until the timeline for Normandy 2's release becomes clear. No point putting together lots of new features that we'll have to rebuild anyway on a new map. But when Normandy 2 is released we're planning to look at ways of using Combined Arms' JTAC features for player-directed airstrikes. Human controllers guiding human pilots into precision strikes on the enemy front lines. What we'll probably do is use one of regular One Life missions (our one-off series of historical missions, e.g. bomber escorts or air support for major set-piece ground battles) to trial this later in the year. Incidentally, if you're interested in the One Life missions or the One Life campaign that's currently running do join the 4YA Discord to find out more. https://discord.gg/4ya We actively encourage text chat too! The server rule is pilots must use either SRS or text chat (or both). There are quite a lot of active and regular pilots whose spoken English is not very good but who can write quick text messages to their team. (hello Jäger squadron!)

I too have a dream. In that dream, people who say things like "I don't like your server, you should scrap your unique formula and copy My Favourite Server" simply go away, and never bother us again. I hope you will share my dream, and play your starring role in it.

Those Israeli liveries look great, really eye-catching. Especially the yellow one, reminds me of the original prototype yellow scheme. Some Canadian liveries would be cool to see given how many FB.26s (basically the Mk.VI but built in Canada at Downview) were made. And of course some 2TAF schemes to represent the European war where the Mosquito distinguished itself, but part of the joy of aviation is learning about the wide and sometimes very obscure variety of places that aircraft ended up in.

Looks like missing textures. Might be cured by running a repair of your DCS install.

Glad to hear you're enjoying it. Most of the mission information is on the website (see my sig block) and in the in-game briefing (default keybind LCtrl+B to view). The F10 map has all the ground targets marked, either as small areas or general locations for search-and-destroy objectives. Some missions have moving ground convoys that you need to find, ID and attack. Others have random convoys with their rough location given in the briefings. But performance is always a consideration, so we can't blanket the map in units - although with multithreading expected later this year we hope that'll give us more overhead to expand the number and type of units in each mission. AI does indeed fly when server population is low. There are also AI bomber raids and the occasional ground strike too. Maps... see the website, under the mission info page you'll find a downloadable JPG of the map marked up with common server slang terms for various locations. Flight planning isn't the easiest, admittedly, but that's a general DCS thing. There is also a historically accurate map as used by the actual WW2 pilots linked further back in this thread.

Bring the revs back for cruise. You'll find that improves the situation as lower revs alters the achievable boost for a given throttle setting. The aircraft wasn't designed to be flown at 3000rpm all the rime.

Think of the big red lever next to the Spitfire IX's throttle as another on/off switch. There is no "rich" or "lean" setting as such. Forward = engine will run, aft = engine will not run. Technically it is called the "carburettor cut off". As grafspee says, you prime the engine before starting because it needs a fuel-air mixture to burn. When the engine is stopped, the parts that produce this mixture won't do so in the correct proportions. Hence we have a manual primer pump. When the carb cutoff lever is forward, fuel can flow from the carburettor into the cylinders. If the lever is forward when you press the starter button, this results in the cylinder being flooded with fuel from the carb. In DCS you see yellow flames coming from the exhuasts as unburnt fuel is pumped out and ignites: you have flooded the engine with too much fuel for it to start and run. The Ki-gass primer pump squirts a fuel-air mixture into the cylinders via the induction system (basically, the fuel delivery lines downstream of the carb). Befire starting the engine you also need to prime the carb with fuel by pressurising the fuel system upstream of it with either the electric pump or the wobble pump. This is why you start the Spitfire and P-51 with the carb cut-off closed until the engine coughs and splutters. That initial coughing is the engine burning the fuel you squirted in from the primer pump: turning on (pushing forward) the carb cutoff at that point gives the engine a steady supply of fuel and air. (In reality you're meant to keep pumping the primer after opening the carb cutoff, until the engine catches and runs steadily. This is not modelled in DCS) The Spitfire LF.IX's engine, the Merlin 66, (and the P-51's almost identical V-1650-7) is fitted with a carb that automatically selects the right fuel-air mixture for whatever throttle (boost) setting the pilot has picked. On earlier Merlins the carb did not do this, so the pilot had to select rich or lean as necessary. The lever used to do this in early Spitfires was the same one we use in the Spitfire IX to turn on or off the carb fuel supply. In those earlier Spitfires there was a separate cutoff control, a ring pull on the right hand side of the instrument panel. The Merlin 66 runs lean up to +7lbs boost and rich over that figure - in game you'll see this as the boost setting being very sensitive to throttle movements until increased past +7lbs.

A smoke bomb would be most excellent, as would the flare pistol.

Have you checked your stick is registering as properly centred when neutral? Full nose down trim should bury you into the ground in no time.

How are you warming up before you get bored and set 2000rpm? Starting at inch-cracked for ~800rpm until oil pressure drops below 120psi, then opening up to 1200rpm gives me the right Ts and Ps after 5 minutes or so. Don't forget the power checks (throttle up to 0lbs boost, exercise the prop through its range twice, check mag drop, 30s with supercharger test button pushed) - normally after completing all of that I'm at 40C oil temp and good to go.

A Happy New Year from the 4YA Project Overlord team! Here's a little look at what we'll be working on in 2023: https://projectoverlord.co.uk/blog/2023/01/01/happy-new-year-from-the-project-overlord-team/

This continues to affect the current Open Beta build.

I think grafspee and Yo-yo are talking about two separate things. Grafspee talks about the 80C minimum *oil* temperature. Yo-yo talks about the minimum *coolant* temperature. On the Packard V-1650-3 and -7 engines, which are licence built Merlin derivatives, the minimum coolant temperature is 60C because at that temperature the coolant return circuit warms the carb air intake enough to prevent carburettor icing on takeoff. I don't yet know for certain but I'm pretty sure the Merlin 66 has the same automatic carb heat arrangement. We are unhappy at the Spitfire oil temp and pressure because according to the Pilot's Notes manual for the real aircraft, oil temp should not fall below 80C due to a thermostatic valve in the *oil system* that cuts out cooling below that point. The schematic for this is in the DCS Spitfire IX manual in this thread.

We're seeing a recurring bug on the 4YA Project Overlord server where trucks no longer refill some types of flak unit. This affects the British Bedford truck, the Third Reich Blitz truck, the Germany Blitz truck and whatever the US equivalent truck is called. It appears that heavy flak (so TR Flak36/Flak37/Flak41; Germany same unit names) no longer refill their ammo supply when the truck is nearby (on F10 map view, the units are within the truck's black circle). For the British and US coalitions, 37mm and 40mm Bofors guns will not refill their ammo supply. In all cases this applies whether or not the truck is part of the same group as the AAA units. This affects the latest 2.8 Open Beta build: v 2.8.33006 Steps to reproduce (sorry, no time to produce a track at the moment): 1. Select the Third Reich coalition. Place a group of the following units: 1x Kdo.40; 2x Flak36; 2x Flak 37; 1x Opel Blitz. 2. Create a target aircraft for the Third Reich unit to fire at. Make it invulnerable to ensure the flak units run out of ammo shooting at it. Expected behaviour: the flak units slowly refill their ammunition while the truck is nearby. Actual behaviour: the flak units run out of ammo and the presence of the truck has no effect.

I'm not sure the engine should exceed 90psi in normal operation unless it's very cold. The main oil pressure relief valve in the Merlin V-1650-3 and -7, as well as the Merlin 68 and 69 (all Packard built 60 series Merlins, almost identical to the M66 in the Spitfire IX) operates at 90psi to divert oil from the main lube oil circuit to the low pressure circuit via a low pressure (I.e. reducing) valve. The diagrams and system descriptions I have access to in the RCAF V-1650 service manual aren't very clear about how these interlinked circuits operate, or where high pressure oil goes if the low pressure circuit is fully pressurised already. Like you, my real world experience is oil pressure starts at 0 and rises when a cold aero engine is started. The Spitfire in DCS is roughly correct at the moment even though the numbers are all wrong (when you start the engine its oil pressure rises, peaks and then slowly falls as temperature rises). The Mosquito modelling after the recent cooling revamp is completely wrong (oil pressure goes off the scale and stays there, eventually settling at 120psi indicated). Let's hope if the Spitfire cooling is updated that it isn't just copy and pasting wrong numbers and behaviour in again.

The reason you crack the throttle is partly for greater fuel flow but also to give the pilot a clear indication of when the engine has caught and the starter motor can be disengaged. Forgot to crack the throttle starting a motor glider once. I was quite surprised when I turned the key away from start and the engine kept turning on its own!

I'm not surprised people think the Fw190A is a terrible air-to-air aircraft. The instant action dogfight missions start you at a substantial disadvantage in speed and height and with a wingman who seems to be of a very low skill level.

It seems most likely to me that the intended point of failure within the flap system during an overspeed is one of the hinge pins in the torque tube linkage assemblies - in fact given the lack of a pressure relief valve in the flap sub-system, I'm sure the pins must have been designed to shear at a given load, that load being well below overpressure and failure of any hydraulic system component in the flap circuit. The alternative is flap overspeed causing total hydraulic system pressure loss through catastrophic component failure, which is not something a sensible designer would choose. Once that pin shears, the flap system cannot be commanded by the pilot or the flap control valve self regulating mechanism. Nothing holds the flaps in place so they, er, flap around. It doesn't matter if that's smooth or not, though it would be a big coincidence if the pins for both sides sheared at exactly the same moment. Suggested feature change for the P-51: Flap overspeed scenario. Current ingame behaviour: The flaps are smoothly pushed back up by airflow during an overspeed. The flaps gradually move back to their selected position when airspeed drops below the overspeed point. The pilot can select the flaps as normal after aircraft speed drops below the overspeed point. No damage is caused to the hydraulic system. Desired behaviour: the flaps are suddenly and sharply pushed back up by airflow. This should be assymetric at slightly different speeds per side. The flaps remain up until airspeed drops below [some plausible speed, maybe 100mph?]. At that point they gradually extend, uncommanded, unless speed increases again. The flap system is destroyed by overspeeding. The pilot can move the flap selector handle in the cockpit but the system does not respond. No damage is caused to the hydraulic system.

Seems about right. Wikipedia says the Samuel Chase has a draft of 8.1m, whereas Dunkerque harbour varies between 7m and 9m deep depending on tide. See http://www.worldportsource.com/ports/portCall/FRA_Port_of_Dunkerque_385.php If you squint at this low-res chart extract the waters around Dunkerque harbour are very shallow in places.

I have done some more thinking about this and actually I think the way it is modelled in-game is almost right. To move from abstract discussion of real world systems to how failures work in DCS: 1. The failure mode for flaps after an overspeed should be sudden failure of the flap system to keep the flaps at their commanded position. The flaps should be pushed by airflow back to the fully retracted position when the system fails. This is already modelled in-game as the flaps being blown back up during an overspeed. 1a. What component of the flap system fails first in an overspeed scenario? The hydraulic system can accept very high pressures: the P-51 E&M manual mentions applying 2000psi from an external source during some test procedures. Therefore it seems likely that in an overspeed, a physical component in the flap system will fail (break) first rather than the hydraulics. I guess perhaps one of the hinge pins in the torque tube arm assemblies (figure 155, in Magic Zach's first post) would be a likely point of failure. Perhaps a check valve upstream of the flap selector valve (FSV) might fail if an FSV poppet is forced open by backpressure from the flaps, but I find this unlikely. 1b. Once the flaps have been oversped and blown back to the retracted position, the flap system cannot be used again. Is this modelled in DCS? If so, then in my view the flap system overspeed scenario is correctly modelled. 2. After an overspeed causes failure of the flap system, the flaps should droop at low airspeeds. This seems to already be modelled below 100mph.

I'm inclined to think @Magic Zachis right. P-51D E&M manual here: https://ww2aircraft.net/forum/threads/mustang-manuals.9051/#post-241325 Hydraulic circuit is split between PDF parts 1 and 2 and some pages are out of order, very annoyingly. Figure 309 (pp264, PDF part 1 page 292, copy attached below) is the main hydraulic system schematic. It shows two check valves fitted to the main system reservoir. It also shows check valves fitted to the supply and return pipes immediately upstream of the flap selector valve. Figure 329 (pp284, PDF part 2 page 13, copy attached below) is the flap system schematic. It starts from the flap selector valve and shows everything downstream of it. There are no check valves downstream of the flap selector valve, just a flow restrictor. -- When the flap system is in a steady state (i.e. flaps are stationary at their selected position) all four poppets in the flap selector valve are closed, as shown to the bottom right of Figure 309. This means hydraulic fluid cannot flow. Therefore air pressure on the flaps cannot back drive the system through the flap operating strut shown on the right of Figure 329. In this scenario an overspeed should lead to hydraulic overpressure in the flap system downstream of the flap selector valve. The flaps will press on the operating strut until something gives way. If I've understood the schematics correctly, the only place for excess hydraulic pressure is bursting one of the pipes or joints shown in Figure 330 (attached). The schematics do not show any pressure relief valve downstream or inside the flap selector valve, a partial exploded drawing of which is at Figure 331 (attached). This should lead to total loss of hydraulic pressure. Edit - but that depends on the max pressure the flap system will accept before catastrophic failure, which must be a design feature of the system and also depends on airspeed. It seems sensible to me that the flap system will withstand pressures well above those in the pilot's notes. Expressed in a different way, the system must withstand the max flap limiting speed plus a safety margin.

What's the TLDR?