Friedrich-4B
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Posts posted by Friedrich-4B
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As I said before I am not going to get into tit for tat about the information that we use for making the FM for the Spitfire.
This is not something that we will get into a mass debate with, tbh we can put points across all day long making cases for one side or the other.
We have our established data that we are using for the Spitfire, at the moment we are looking at 21lbs, although this may change to 25lbs during development depending on how things go. It will not be an 18lbs boost Spitfire.
We have spoken previously Kurfurst that historical data is only so reliable, it is not subject to verified testing conditions and we have verified our testing data with a number of warbird pilots, one of which actually tested a couple of theories of mine during a currency flight in a MkXIV.
There will always be variances and we as a third party primarily have to satisfy ourselves that our data is accurate and as reliable as possible.
It should be underlined again that we have no interest in the combat performance of the Spitfire vs other modules, there is no tit for tat stuff going on here. In fact I dont think any of our dev team regularly participate in combat in DCS. So our sole interest is getting an FM that represents the aircraft as accurately as possible within the above constraints.
Pman
:thumbup: Looking forward to flying this beauty (or would that be the beast?) once she's available. :pilotfly:
Purely for interest, I've attached a 1944 Flight magazine article on the XIV, as well as a 1945 Flight article on the Griffon 65.
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Quick question: Is the XIV able to cool the engine and oil more efficient than the IX that we got?
The Griffon had more effective lubrication than the Merlin; eg:
...end-to-end, high pressure lubrication of the crankshaft (Special Features page 3 of the attached article; also Main Cooling - starting on page 6 - and Lubrication page 7)and a better coolant system, so, overall, the Griffon was an easier engine to manage in respect to engine temperatures.
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Indeed! :huh:
Certainly goes against some of the things I have read from the actual test pilots! :music_whistling:
I recall a report from a test carried out at various altitudes which stated that up to ~25000ft the manoeuvrability increased, due to the roll rate presumably, and that the clipped spitfire was able to shake off the normal spitfire up to that altitude.
Yes slightly slower climb rate and improved dives, I imagine the dive was only an initial improvement.
There were conflicting opinions and conflicting flight test results - mainly on Mk Vs - as to how effective the clipped wings were: in some cases, it was down to the personal preferences of the pilots.
AFAIK, for 2 TAF Spitfires especially, the clipped wings helped relieve some of the bending stresses incurred on the outer wings during dive/glide bombing attacks. Most of the Mk XVIs had clipped wingtips, as did many XIVs; not sure of the ratio of L.F. Mk. IXs with clipped wings cf normal wings.
@SithWe will never see a IX with HF wings it had a different engine Merlin 70 IIRC and given the things I read from Jeffery Quill moaning about the extended wing tips we are not missing anything! :D
Yep, those extended wingtips were hardly worthwhile, considering their disadvantages outweighed whatever small advantage they offered in climb rate at altitude and any possible increase in service ceiling.
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I like the idea... but it can be improved.
What if the mission make could set the ALG's presence on the map based on various triggers.
Then, it might be possible to simuate a "faster than" , or "slower than" historical invasion campaign - and progress could be based on how the players achieve various objectives.
Wonder if it would be possible for the Germans to shell some ALGs for a few weeks after D-Day, just to make life even more interesting..? :smilewink: :pilotfly:
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On the issue of the Spit burning less fuel than the Mustang at similar settings, does anyone have the rates for the Mk XVI? That Mark used (I believe) the same Packard Merlin as the contemporary Mustang production blocks. As I recall, the Packard Merlin used a different carburetion system from the Rolls Royce versions.
The carburettor (Stromberg PD-18A-1 in Packard vs Stromberg 8D/44/1 in R-R) made no noticeable difference to the fuel consumption of the Spitfire XVI cf the IX.
I would have expected the draggier Spit to burn more fuel at the same engine settings.cheers
horseback
Obviously not, according to the fuel consumption figures noted in Pilot's Flight Manuals and Pilot's Notes, some of which have been shown in this thread, and in several other threads discussing the P-51D and Spitfire. Yo-Yo's comments on why this was seem to be the most logical explanation as to why the Mustang had a higher fuel consumption.
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That would mean the merlin in the spit run hotter at the higher boosts compared to the mustang?
Spitfire L.F. Mk IX: maximum allowable coolant temp = 135° C. @ +18 lbs @ 3,000 rpm (Oil = 105° C.)
P-51D: maximum allowable coolant temp = 121° C. @ 67" Hg @ 3,000 rpm (Oil = 105° C.)
Presumably the addition of the 85 gal rear fuel tank in later P-51Ds also allowed more latitude for the increased fuel flow rates, compared with the D-5.
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Returning to the roots of this consumption figures I found very interesting thing: the same carburettor for V1650-7 metered 15-20% more fuel than for Merlin... so I can suggest that mixture was readjusted for Spitfires regarding the lack of fuel onboard...
Another interesting detail is that the P-51D-5 Pilot's Notes, dated April 1944, shows a consumption rate of 194/187 U.S Gall p/h @ 67 Hg @ 3,000 rpm (162/156 Imp Gal p/h)
Whereas the P-51D/K Training Manual, printed August 1945, shows the 211/215 U.S Gal p/h @ 67 Hg @ 3,000 rpm mentioned by Kurfurst (176/179 Imp Gal p/h)
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Excellent! :thumbup::thumbup:
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Eee ooohhh arrr! Great work. The colours look fantastic and should lend themselves to other desert or Italian based Spitfires.
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Friedrich...........I am in not in a position to argue with you about this,as I was not around during the years 1943-44 to witness the said aircraft for myself,and I'm sure the red maple leaf was the most popular emblem with the Canadians.
However,this was my thread,that I started,and the pictures given were how I would like my choice of Johnny Johnson's skin depicted,with a green maple leaf,and at the end of the day that's all it is,an aircraft skin for a PC simulator.
I do not want to rewrite history here,and yes your information is useful,no one is denying that,but I rather think your taking this far too literally friend.
This forum is for requesting skins,and all I am doing here is just that,requesting a Spitfire skin as the pictures depict.....simples :)
:yes: Okay, you've got me there; one of my hobbies is model building, which means I can be a pain in the neck when discussing colour schemes and markings...old habits, etc etc :smilewink:
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Friedrich.....are you aware that there were a number of variants of Johnson's Spitfire IX with the code JE J ?.....because he was a Wing Commander he was entitled to sport his initials in the code.
I have long been aware that Johnson used two or more IX's with his initials JE-J, and that MK392, in particular had several variations in its colour schemes and markings during it's lifetime.
The Spitfire IX I have been uploading pic references for definitely sported the Green Maple leaf,it has been well documented,this was when he was OC of Kenley Wing during the Spring of 1943,however on later variants his Spitfire did sport the Red version."Definitely" is the wrong word to use when there is still a great deal of contention among aviation historians and other enthusiasts as to the colour of the the maple leaf on EN398:
What specific documentation(I'm not talking about art work), apart from Johnson's account in Wing Leader, supports the Green maple leaf?
I'm not saying Johnson was wrong; all I'm saying is keep an open mind when it comes to
the specifics of aircraft colour schemes, particularly the smaller, personal emblems.
This is probably why you are questioning my references,his Spitfire IX which sported the D-Day black/white stripes had the Red Maple leaf for a start,and this is when he was OC with No 144 Wing stationed at Ford in June 1944,so there were different versions,with different Maple leaf emblems on,but all with JE J as the code.I wasn't questioning your references, I was pointing out that other researchers have a different POV and that I tend to agree.
I have also pointed out that the red maple leaf was by far the most popular emblem used by Canadian units, and that the Canadian government issued specially made decals to RCAF squadrons.
This, I would have thought, is useful information for those wanting to develop Canadian themed skins for the L.F Mk IX.
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No red herrings, my point is clear. I think I remember it was discussed and stated it was 44. I'm not wasting time perusing the whole forum. If you are so sure about your date, please just tell me where I can check it, tell a source, or something. Otherwise I'm sticking with the date I think I remember (though my memory sometimes slips for sure).
S!
Production of the Supermarine built Spitfire L.F. Mk. IXs started in February-March 1943,
beginning with EN529 - 583, after which production was concentrated on Mk VIIIs, including several hundred L.F. Mk. VIII w/Merlin 66, built in 1943.
Castle Bromwich production of the L.F. Mk. IX started in August 1943,
* beginning in the MH35xserial range:
* then MH612 & on, alongside of Merlin 63 F. Mk. IXs:
*MH813-MJ516 alongside of Merlin 63 F. Mk IXs (September - mainly October '43):
*MJ16x - MJ428 serial range (October/November '43):
* MJ441-MJ698 (November-December '43:
* MJ712-MJ942 (mainly December 1943).
All Merlin 66s were able to use +18 lbs boost right from the start. So, no, the so-called "LFIX Merlin 66 @ 18lbs boost" was not built only from 1944 on.
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Can anyone confirm that it is the wrong kind of radio for the era or that if HF is contemporaneous with the time period in question that we should have a wire aerial to go with it?
Interesting information about the PTT from Sokol1_br. So there should be an active Tx/Rx switch on the unit itself.
It can definitely be confirmed that the TR 1143 was the standard R/T fit for Spitfires, starting in 1942: the exceptions were Spitfires that were given to the USSR and some other countries.
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The germans measured real G loads as well during combat missions and established a nice tree graph with G-loads vs incidence. A lot of weird things being said in this thread anyway...
Comparing static G load trials with real life loads is pretty useless, these were done to compare with factory spec static loads. The most stress will be caused ba asymmetrical loading and torsion of the wings. Also in WWII there were quite some cases where resonance caused an otherwise sound structure to collapse, simply because certain things were not known at the time. I think people proposing 20 G limits cant possibly know what this would mean from an engineering point of view. Thats pretty crazy for a flying structure with non modern alloys nor honeycomb structures..
Indeed, there some weird things being said in this thread, which is why, perhaps, you didn't get the joke about 20 G. :music_whistling:
My main point was this:
Nobody has yet posted any reliable figures on the Spitfire L.F. Mk IX's limitations....I have no doubts that Yo-Yo has more information about the IX's G limits than all of the rest of us combined. -
but what I would really want, is the heavy distortion found in the 4 fwd panels, which is in the real Spit and would add to realism.
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That distortion only applied to the early windscreens fitted to Mk Is, IIs and VA/VBs: these had curved side panels and an external bullet-resistant windscreen: (Spitfire VB, Flt Lt Eric Lock, 611 Sqn, July 1941.)
From the VC series on, the structure was composed of optically flat panels, including the internal bullet-resistant windscreen: (Spitfire L.F Mk. IX, Sqn Ldr John Plagis, 126 Sqn July 1944)
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An article on the effects of G-forces on pilots, written in the September 1945 issue of Flying Magazine, can be found starting here (page 50) and continuing here, on page 92: the article, which continues to page 96, is well worth a read.
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Anyway, here is the page from the Spitfire II manual addressing this issue
That page looks to be from a set of Spitfire II training notes, dated June/July 1940 which do indeed mention a 10 G limit.
However, as noted in a page posted by Hiromachi, in 1940 wings that had already been damaged didn't fail until 12.3 and 13 G respectively (800 mph @ 6,200 lbs) so the jury's still out on a 10 G limit
In addition, the Pilot's Notes General note that the limitations noted often had a safety factor of 2; thus 10G in a set of pilot's training notes could well mean 20 G - see Introductory para (ii) ...
continuing with section 2 Limiting Speeds (i) Diving
Nobody has yet posted any reliable figures on the Spitfire L.F. Mk IX's limitations, apart from some speculative comment about the limits being no higher than earlier Spitfire marks. But, as it is, I have no doubts that Yo-Yo has more information about the IX's G limits than all of the rest of us combined.
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I didnt state it does or it should, merely that manual warns, as it does warn indeed - about use of controls with care.
It would be interesting to find out those reports mentioned on the picture carried by Accident Branch at Farnborough.
No problem - I was agreeing with you, but also disagreeing with an earlier claim that had been posted, to the effect that the structure failed at around 10 G because of the elevators alone: there is nothing in any Spitfire manual that "explicitly" says that. :smilewink:
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Manual warns indeed, but it doesnt mean that wings break exactly at 10 G. Usually manuals set more conservative numbers to protect both pilots and machines. Nothing unusual would be in this department.
Nor are there any Spitfire "manuals" that specify 10 G as the structural limit. Without any such evidence, it's just pure speculation that Spitfires invariably broke up at around 10 G because of the elevators alone.
Here are details of the IX's wing construction from
Spitfire Mk IX & XVI Engineered:
Though I think I already posted that one some time ago:It would be actually interesting to know what load was reached when OP broke his wings, personally so far I managed to do so once by silly maneuvering but that was at very beginning. Since then not once they broke and I still insist that before one would approach the load to damage wing spars pilot would already be unconscious.
The usual average WW 2 pilot could blackout between 4 to 6.5 g, depending on the pilot and the cockpit environment: unconsciousness could occur without warning during high speed pullouts etc of 3 to 10 g.
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Good research.
I think that covers my question...
Thanks for all your work on this Friedrich-4/B, my curiousity is well satisfied. To celebrate, I repeated my earlier trial in the Free Flight IA mission, this time leaving the boost pump ON. No problems at all, clawed my way up to 41,000 w/o a hiccup, even w/o switching on the fuel tank pressurization.The DCS Flight Manual and Quick Start guide could each benefit from some attention in this area. The fuel system description makes no mention of the electric boost pump at all, nor does it appear in the various checklists for start-up, warm-up, climb and landing. It's ON by default in all the IA missions which begin with the engine already running, so clearly someone appreciates its importance.
Glad to be of help; I struck the same problem during one of the few flights I've been able to make (with Christmas and holidays and trekking around, visiting relies etc) and figured it had to be vapour-lock. It shows how well ED's developers have replicated the Spitfire.
And, yes the boost pump and vapour-lock would be worth a mention in the flight manual and QS guide: that should stop the air in computer rooms turning blue and vapourizing. :smilewink:
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A bit of background to this: many early Spitfire F. Mk IXs with Merlin 61s were fitted with an automatic tank pressurizing valve, plus a fuel cooler fitted in the port wing root. From the Spitfire IX (Merlin 61) Pilot's Notes, August 1942:
Paragraph 6:
With the Merlin 66 and its Stromberg Injector carburettor, the fuel pressure was increased from c. 8-10 lbs/sq. in. to 14-16 lbs/sq. in. plus the fuel system was modified on all but the earliest L.F. Mk. IXs* to include the booster pump in the lower fuel tank.
*This means those L.F Mk IXs that were built by Supermarine from February 1943, in the EN529-EN637 range http://www.airhistory.org.uk/spitfire/p036.html range.
The mass production of L.F Mk. IXs started at Castle Bromwich in July 1943, in the MH3xx range http://www.airhistory.org.uk/spitfire/p063.html - in the interim, priority had been given to building the L.F. Mk. VIII w/Merlin66.
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More or less the same as you, so this just leaves the question.
Why can't the pump supplied by RR with their engine, get past about 18,ooo'?
A simple hole in the tank or pump failure would stop the engine when flying at even medium altitudes.
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The fuel tanks were pressurized to prevent vapour lock: as blue_six discovered, entering a climb with tank pressurization off led to his fuel boiling and developing vapour lock, which doesn't necessarily register as low fuel pressure.
From FAA Regulations: Chapter 14: Aircraft Fuel System:
Vapor lock is a condition in which AVGAS vaporizes in the fuel line or other components between the fuel tank and the carburetor. This typically occurs on warm days on aircraft with engine-driven fuel pumps that suck fuel from the tank(s). Vapor lock can be caused by excessively hot fuel, low pressure, or excessive turbulence of the fuel traveling through the fuel system. In each case, liquid fuel vaporizes prematurely and blocks the flow of liquid fuel to the carburetor.Aircraft gasoline is refined to have a vapor pressure be between 5.5 pounds per square inch (psi) and 7.0 psi at 100 °F. At this pressure, an aircraft fuel system is designed to deliver liquid fuel to the carburetor when drawn out of the tank by an engine-driven fuel pump. But temperatures in the fuel system can exceed 100 °F under the engine cowl on a hot day. Fuel may vaporize before it reaches the carburetor, especially if it is drawn up a line under a low pressure, or if it swirls while navigating a sharp bend in the tubing. To make matters worse, when an aircraft climbs rapidly, the pressure on the fuel in the tank decreases while the fuel is still warm. This causes an increase in fuel vaporization that can also lead to vapor lock. Various steps can be taken to prevent vapor lock. The use of boost pumps located in the fuel tank that force pressurized liquid fuel to the engine is most common.
Once blue_six pressurized the fuel tank, the fuel began to settle down, but the condensing fuel had more than likely left water in the system, that began to form ice crystals at high altitude. Result = low fuel pressure and an embarrassing silence...
As fuel vaporizes, it draws energy from its surroundings to change state from a liquid to a vapor. This can be a problem if water is present. When fuel vaporizes in the carburetor, water in the fuel-air mixture can freeze and deposit inside the carburetor and fuel induction system. The fuel discharge nozzle, throttle valve, venturi, or simply the walls of the induction system all can develop ice. As the ice builds, it restricts the fuel-air flow and causes loss of engine power. In severe cases, the engine stops running.In other words, keep your fuel tanks pressurized, and the fuel booster pump installed in the fuel tank is also there for a good reason. :smilewink:
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Agree, not a good example, nor is the schematic you've linked us to entirely clear. My money is on the priming line running around not through the boost pump, given the way the two segments line up perfectly on either side of the pump. This isn't a biggie, either way. What we still don't know for certain is why we can't obtain a good engine start in the sim when we move the idle cut-off control forward prior to priming and hitting the start and booster coil buttons, per the sequence set out in the RAF Pilot's Notes. Is it an inherent limitation of the sim, or a bug that can be squashed?
There seems to be some confusion here, probably because the language in the 1946 IX/XI/XVI Pilot's Notes is confusing: I would suggest ignoring those notes
Put simply:If the cut off control is opened(ie: pushed forward) before the engine fires, all you're doing is flooding the engine!
These pages are from the Spitfire VII/VIII PN's, dated December 1943: these state quite clearly that the idle cut out control is opened (pushed forward) after the engine fires, and certainly not before priming the engine!
Here are the pages from the Merlin 60-85 series Maintenance manual, January/July 1944: idle cut-off control open (pushed forward) after the engine has started.
There's nothing complicated or buggy about ED's starting sequence.
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No problem Jocko....what i would say is,if anyone has any further picture references for Johnson's EN398,please feel free place on this thread :thumbup:
A very useful article on EN398 can be found on here, The Spitfire Site. Note that one reader has commented on the Maple Leaf insignia:
However, the maple leaves you depict are not correct. You show the 1965 heraldic maple leaf from the modern Canadian flag. Johnson would have used the type of leaf insignia common to the times, more naturalistic in its design, whether red or green.According to Canadian researchers from an outfit called Aviaeology, it would seem that Canada supplied maple leaf decals to its overseas RCAF units, which would surely have included Johnson's Canadian squadrons.
All of the decals were red maple leafs, not green, so I would argue that EN398's maple leaf was red.
Below are some of the "1st generation" (14 & 14a) and "2nd generation" (15 to 15d) maple leaf insignia styles used by RCAF aircraft (NB:from one of Aviaeology's decal sheets AOD48005 Canadians in Fighter Command #1: RCAF Mosquitoes, featuring Mosquitoes of 418 Sqn.)
A close look at the photo in Basco1's post shows that Johnson's maple leaf was similar in style to 14 or 14a. (There also seems to be some wear/light exhaust staining.)
Also note that EN398, being a very early Mk IX, retained the teardrop shaped upper ID light behind the aerial mast.
DCS: P-47D-30 Discussion
in DCS: P-47 Thunderbolt
Posted
Fortunately for the pilots, the D-30 series on were fitted with "Compressibility Recovery Brakes": if deployed properly, they assisted the pilot by reducing the dive speeds, thus reducing the likelihood that the pilot would lose control. The P-47D pilot's manual states that the main problem with the aircraft in a dive was the tendency for the nose to "dig in" ie; go nose down. The recommendation was to keep the aircraft trimmed for high-speed flight before entering the dive.