I agree, nominal (mil) power output of MK9D in-game seems okay, a bit conservative at some altitudes but reasonable (there are documents with high and low numbers).
I often see documented static SL WEP output of MK9D at 2100 or 2130 hp. Along with 2030hp from that book.
The top speed performance of J7W1 in-game is rather inferior to the calculation, especially at SL.
Where is this stated, though? That is interesting
The vmax topic is more complicated.
All sources point to that our version should do 593kph at SL and 740kph at 8400m.
But in what powers? This is not clear because I cant find the regime of ram at what the power of the sources are archived.
First we dont know if 594kph is at WEP or 100% since this is not specifed anywhere.
About 740kph at 8400m:
1. If military power 1660HP at 8400m is at 0 ram:
Then the vmax cant be at the same alt because with ram air crit alt will increase above 8400m, the vmax at military will be higher than 8400m and will be similar to what we have in game (around 10km).
So 740kph is not the speed achieved at 1660hp of military if this power is at zero ram, 740kph at 8400m will be the speed achieved at a higher power of WEP because a higher power decreases crit alt. With this logic it makes sense that 594kph is at WEP too.
This is similar to what we have in game:
In game data 0 ram:
100%: 1850hp at 2000m / 1660hp at 8400m
WEP: 2150hp at 2000m / 1980hp at 7400m
In game data at 740kph:
100%: 1660hp at 9800m
WEP: 1980hp at 8400m
Speed of J7W1 in game with this power:
100%: 564kph at SL / 739kph at 9800m
WEP: 594kph at SL / 756kph at 9000m
2. If military power 1660hp at 8400m is at vmax ram:
Then it would make sense that 740kph 8400m is the speed achieved at 1660hp at 8400m.
This would mean that overall the power is too high in game and with this logic is not clear if 594kph is at WEP or 100%.
If 1660hp at 8400m is at vmax ram we would get this powers (aprox):
0 ram:
100%: 1850hp at 500m / 1660hp at 7000m
WEP: 2150hp at 500m / 1980hp at 6000m
740kph:
100%: 1660hp at 8400m
WEP: 1980hp at 7000m
With this we would get speeds around:
If 594kph is at 100%:
100%: 594kph at SL with 1700hp / 740kph at 8400m with 1660hp
WEP: 630kph? at SL with 2030hp / 750kph at 7000m with 1980hp
If 594kph is at WEP:
100%: 570kph at SL with 1700hp / 740kph at 8400m with 1660hp
WEP: 594kph at SL with 2030hp / 750kph at 7000m with 1980hp
From my point of view I think the case 2 is the most realistic, with 594kph being the speed at 100%.
But there are a lot of asumptions like:
What is the power at crit alt of WEP?
What is the speed at crit alt of WEP?
What is the 0 ram power of WEP and 100%?
What is the speed at SL of WEP?
What is the power at SL of WEP with zero ram?
So taking in account the little info we have I think J7W1 is fine in game and could only be changed with new and better info. And if it is proven that case 2 is correct then it would be only be a buff for SL speed and it would be a big nerf to high alt performance.
Ah I thought you meant that this was the method of the historical calculation. In that case the vmax is pretty inferior to the calculation, of course it’s fine for some liberty from a calculation of a plane that never demonstrated speed.
I’m pretty sure they are. There are multiple historical documents with such various power outputs specifically for the Model 42. The Ha-43 was still very much in development by the end of the war, so it is expected. One of the figures ‘2030’ or ‘2130’ could definitely be a repeated misprint, but I find 2100 a lot as well.
I do think all the speeds given are at military power, as per standard. It would be strange to provide the calculation at WEP because Japanese engines, particularly late war, were often not reliable to use WEP for some period of time.
I attached here part of the prototype performance outline chart, highlighted is J7W1’s box. As we know, normally the mil-power full-pressure output of -42 is listed at 8,300, or 8,400 meters (some documents even 8,500). Here in the context of J7W1’s flight performance, it is written 1,660hp @ 8,700 meters.
Perhaps this could be a figure considering ram effect, it does correspond to the J7W1 vmax at 8,700 meters of 750 km/h.
(In your comment you wrote vmax is at 8,400 meters, but I think most sources give vmax at 8,700 meters.)
Mind two replies, just attaching a figure for 2,100 TO-HP of Ha-43-42:
I would consider this document to be giving the “higher end” of output figures, 1900hp @ 2000m, 1750hp @ 8,500m (quite dramatically for the last figure).
It is a document that was prepared after the war for the US by Mitsubishi, though.
This document can be found on the NDL digital collection site, search:
TEST ENGINES, SPECIFICATIONS AND PERFORMANCE. REPORT NO. 16I(7)
That is nice, you are delivering as expected qaz ;)
Very nice.
Is hard for me because I dont know japanese, does it say in any part that power is at full ram?
Or any specification.
Any proof that this documents were specified with vmax ram or that this was common practice would also work.
If we want to change it in game we will need this.
Also about this, it can be the difference between in a testbed and in the plane.
If im correct the j7w1 had a fan to cool the oil radiator right?
Fw190A radiator took about 50hp from the test bed figures iirc
Actually from 60 to 80hp
No, sadly no detail like that. It’s just takeoff HP and in the 1st spec table “Nominal Power / Altitude”, 2nd engine perf table “High-Altitude Performance”.
No proof in these documents. The 1660hp @ 8700m figure perhaps being the power with ram is just a speculation for the sake of this discussion. It’s either that, or it’s an erroneous figure.
Tbh, I am not terribly concerned with altering the performance in-game of J7W1, but I do think it’s a bit modest. And perhaps more related to drag.
Just to lay out the various figures at hand for organization:
(Ha-43-42 has a stepless fluid-coupling supercharger like Daimler-Benz engines)
Takeoff HP (WEP 0m 0km/h):
2030 hp
2100 hp
2130 hp
Nominal (Mil) HP @ 0 m
1730 hp
Nominal (Mil) HP @ Alt Low
1850 hp @ 2000 m
1900 hp @ 2000 m
Nominal (Mil) HP @ Alt High
1660 hp @ 8300 m
1600 hp @ 8400 m
1660 hp @ 8400 m
1750 hp @ 8500 m [goal?]
1660 hp @ 8700 m [ram?]
J7W is not a popular vehicle thus there cant be an angry horde demanding a fix.
But I dont believe there should be an angry horde of players screaming at once to move gaijin to improve stuff.
Im one individual player here calmly suggesting to give J7W the airspawn it deserves because the whole thing is designed as an interceptor. if this suggestion is not valid, I would like to know why.
I am quite sure i saw various requests for this exactly with the same reasoning.
To show you an even easier example - read this about the rejection of a bug report regarding the XF5F interceptor (wt wiki confirm interceptor):
Basically they rejected the bug report (wrong classification of an interceptor as a fighter) and asked for a suggestion - very funny.
Anyway - good luck for your suggestion when they remove the freeze!
This has already been processed as a Suggestion.
300m increase for vmax ram is too little, it has to be something else.
Or 0 ram is below 8000m, or 8700m is 0 ram.
The increased power of the engine test is probably because the j7w1 radiator fan absorbs some of the power, like in Fw190.
J7W1
It lacks flaps and slats on canard wing (already proven and reported MANY times)
Incorrect engine power curve at lower altitude (proven and reported as well)
Lack of interceptor air spawn (TaC and TaH do have it, hence they can live/work at their BR’s, they have, pretty much, same climb rate)
IDK what this discussion and argue with moderator is trying to do. Everything been already reported and proven with this plane decades ago.
Nie wiem po co wyważać otwarte drzwi - I don’t know why break down an already open door
It is, indeed, to niche machine to get any developer attention whatsoever, without big community backlash they do not seem to fix a thing.
Just give up.
And here i am, wasting my keyboard again, what a fool i am.
Where?
I exposed in a clear way how and why it is currently modeled in game in the way it is.
Please read this with attention:
If after understanding the current situation you have any valid point or source please let us know.
It does not matter if it is niche or not.
If there is a problem with it and it can be demonstrated it is worth to report.
Of course 3d model problems are way more complicated to get fixed if it is an old model that needs an entire rework.
But in my experience as a bug reporter and now as a tech mod flight model issues are fast resolved in every case.
FM developers are active in fixing issues.
In some little place that got cancelled with passage of time. I could not care less to look after it now.
I know that you are employed and signed some sorts of documents which will make you talk like you talk.
Employee can not go against his employer after all.
Al-thou i do believe that staying silent would be better than blatant company washing.
It matters.
It already was, more than once.
They might be (there was more than enough time to fix that tho)
2014(15,16 and so on) → 2023 (soon 24) = 9 years. They sure are taking their time, niche nation, niche plane, no profit. Who cares.
