Focke Wulf light fighter

[drgondog]

drgondog - help

Does a laminar flow profile generate less lift than a conventional profile for the same wing, i.e. would the aircraft have a worse climb rate?
The Fw 190 had a high-lift wing profile, IIRC, which generates much lift so that wing area could be kept small.

Like all general comparisons. it depends.

First, the ROC is dependent on GW and Avail HP versus Hp Required. CL range is only important near stall and ROCmax for both FW 190 and P-51 were well within the CL vs Alpha envelope and close to each other.
[above edited - I meant to say weight, not wing loading]

That stated, the NACA 23016 (or 015.5) compared to NAA/NACA 45-100 (~16.13% root, 11.46% at tip) was more interesting in discussing Cd vs CL. The NAA wing was far more efficient in low CL range (low AoA in cruise range) and crossed over with NACA 23016 at approximately CL= 0.55 - which is near CL for best climb rate for both FW 190 and P-51. IN CL range> 0.5-0.6 the FW 190 wing had lower CD as f(CL).

The High Speed/Low Drag NAA wing was neither a handicap for climb or high speed. That said, where a higher CLmax IS important is in a high G, low speed turn.

In any case, the FW 190 should not suffer due to swapping out wing sections.

Recall that Bearcat had a NACA 23018, much thicker than the XP-51F &G, but all had near same ROC.

 

[SaparotRob]

Failure is not an option. It's my default setting.

 

[spicmart]

First, the ROC is dependent on wing loading and Avail HP versus Hp Required.

Does that mean that - everything else being equal - the plane with the higher wing loading climbs worse?
I mean if you compare two planes of the same type just with different wing areas. e.g. Fw 190 V1 k and Fw 190 V1 g.
Pls excuse my laymanship.

 

[Admiral Beez]

How could a Focke Wulf light(er) fighter (based on the 190 or not) have looked like?

I assumed the Fw 190 was a light fighter. Swastika aside, it's almost cute for being so tiny.

 

[marathag]

- it is already bigger and draggier A/C than the 190; scaling it up increases bulk and drag

My goto for fast size comparisons.
The 15% is to scale to the larger diameter of the 14R. Wing doesn't really need to change, other than the strengthening the A6M5c had received
-109 was already small. Really small.
Too small, leading to all the lumps and bumps of the later models, putting 8 pounds of crap into a 5 pound bag.

 

[Shortround6]

Does that mean that - everything else being equal - the plane with the higher wing loading climbs worse?

It depends

Assuming you have everything else being equal like power and weight (power to weight being equal) then we are left with drag and wing area. IF you can get the drag to be the same then wing loading becomes dominate. If drag is not equal then the wing loading might not be the dominate factor.

Now did the Spit IX out climb the 109G-6 because of it's big wing or because had more power and less drag?

Or is there something else going on??????

.."Its rate of climb at 20,000 ft. with the 0.42 reduction gear is inferior to the Fw 190 A and the Me109 G, even when operating at +18 lb. per sq. inch boost.

..................When fitted with the 0.477 reduction gear and at +15 lb. per sq. inch boost the Spitfire is equal in rate of climb to the Me 109 G-2; when operating at +18 lb. per sq. inch boost it is superior to all German fighters at present in service."

If you can not turn the engine power into thrust????

Rate of climb at 20,000 ft: ..................The rate of climb varies according to type of reduction gear fitted. ..................With an 0.42 reduction gear (at + 15 lb. per sq.inch boost) the rate of climb is 2,540 per minute. ..................With the same reduction gear, but at + 18 lb. per sq. inch, the rate of climb is 2,750 ft. per minute. ..................With an 0.477 reduction gear (at + 15 per sq. inch boost) the rate of climb is 2,950 ft. per minute and increases to 3,230 ft. per minute at + 18 lb. per sq. inch boost.

From Spitfire Mk IX Performance Trials

 

[SaparotRob]

View attachment 755578
My goto for fast size comparisons.
The 15% is to scale to the larger diameter of the 14R. Wing doesn't really need to change, other than the strengthening the A6M5c had received
-109 was already small. Really small.
Too small, leading to all the lumps and bumps of the later models, putting 8 pounds of crap into a 5 pound bag.

I love this graphic popping up every now and again. It's a Hoot. Thanks!

 

[Admiral Beez]

I love this graphic popping up every now and again. It's a Hoot. Thanks!

The Russians could be diminutive as well.

Can we consider the Fw 159 to be Focke-Wulf's attempt at a light fighter?

 

[Shortround6]

The Russians could be diminutive as well.

View attachment 755593

Can we consider the Fw 159 to be Focke-Wulf's attempt at a light fighter?

View attachment 755594

Sure, why not.
so was the

trouble was that it was about a dead heat with a Gladiator biplane

 

[Admiral Beez]

Sure, why not.
so was the
View attachment 755595
trouble was that it was about a dead heat with a Gladiator biplane

That looks like a baby Stuka.

 

[GrauGeist]

The He112A looked a bit more like a Stuka junior.

 

[tomo pauk]

The 15% is to scale to the larger diameter of the 14R. Wing doesn't really need to change, other than the strengthening the A6M5c had received

We can take a look at the A6M8, and it's 1500 HP Kinsei as a passable equivalent to the 14R. It was supposed to do 360 mph.
Same for the Ki-100. Do we want a 360 mph fighter in Europe past 1941?

-109 was already small. Really small.
Too small, leading to all the lumps and bumps of the later models, putting 8 pounds of crap into a 5 pound bag.

One of reasons I like the '190 lite' better
OTOH, the 14R would've been a good match to the Bf 109X.

 

[spicmart]

It depends

Assuming you have everything else being equal like power and weight (power to weight being equal) then we are left with drag and wing area. IF you can get the drag to be the same then wing loading becomes dominate. If drag is not equal then the wing loading might not be the dominate factor.

Now did the Spit IX out climb the 109G-6 because of it's big wing or because had more power and less drag?

Or is there something else going on??????

.."Its rate of climb at 20,000 ft. with the 0.42 reduction gear is inferior to the Fw 190 A and the Me109 G, even when operating at +18 lb. per sq. inch boost.

..................When fitted with the 0.477 reduction gear and at +15 lb. per sq. inch boost the Spitfire is equal in rate of climb to the Me 109 G-2; when operating at +18 lb. per sq. inch boost it is superior to all German fighters at present in service."

If you can not turn the engine power into thrust????

Rate of climb at 20,000 ft: ..................The rate of climb varies according to type of reduction gear fitted. ..................With an 0.42 reduction gear (at + 15 lb. per sq.inch boost) the rate of climb is 2,540 per minute. ..................With the same reduction gear, but at + 18 lb. per sq. inch, the rate of climb is 2,750 ft. per minute. ..................With an 0.477 reduction gear (at + 15 per sq. inch boost) the rate of climb is 2,950 ft. per minute and increases to 3,230 ft. per minute at + 18 lb. per sq. inch boost.

From Spitfire Mk IX Performance Trials

Not sure if I get your point.

If I take two of the same airframe (same engine) just with differently sized wings, the one with the smaller wing has less drag so "wing loading might not be the dominate factor". I came that far...
With everything else being equal I also meant engine and its settings.
I guess something's eluding me?

 

[Shortround6]

Not sure if I get your point.

If I take two of the same airframe (same engine) just with differently sized wings, the one with the smaller wing has less drag so "wing loading might not be the dominate factor". I came that far...
With everything else being equal I also meant engine and its settings.
I guess something's eluding me?

You are right in theory.

Problem for us armchair aircraft designers (crayon and paper napkin) is that there is a lot of hidden stuff that doesn't show up in a lot of spec sheets.

Find the specs the explain which Spitfire MK IX was using which reduction gear and especially, what were the differences in the propellers being used?

The other thing is that the Spitfires with different wings could swap places in climb ratings depending on altitude. The clip wing planes climbed better at low altitudes. They were about the same at the middle altitudes and the extended wing planes did better at high altitude.

Spitfires are interesting and yet confusing. The change in wing span was all done it the wing tips, only from the end of the alerions. the change in area itself is minor 231sq ft clipped, 242sq ft normal, 248.5sq ft extended.
What changed was the aspect ratio and flow of air over the wing in the span-wise direction. This changed the overall lift co-efficient of the entire wing (or at least a large part of it).

Edit; Clipped wing 32ft 7in. Normal wing, 36ft 10in. extended wing, 40ft 2in.

Now try to compare different wings on different airplanes. Once we get beyond square footage (gross square footage or net square footage) we need the advice/help of a trained aerodynamicist. Of which I am not one

 

[spicmart]

You are right in theory.

Problem for us armchair aircraft designers (crayon and paper napkin) is that there is a lot of hidden stuff that doesn't show up in a lot of spec sheets.

Find the specs the explain which Spitfire MK IX was using which reduction gear and especially, what were the differences in the propellers being used?

The other thing is that the Spitfires with different wings could swap places in climb ratings depending on altitude. The clip wing planes climbed better at low altitudes. They were about the same at the middle altitudes and the extended wing planes did better at high altitude.

Spitfires are interesting and yet confusing. The change in wing span was all done it the wing tips, only from the end of the alerions. the change in area itself is minor 231sq ft clipped, 242sq ft normal, 248.5sq ft extended.
What changed was the aspect ratio and flow of air over the wing in the span-wise direction. This changed the overall lift co-efficient of the entire wing (or at least a large part of it).

Now try to compare different wings on different airplanes. Once we get beyond square footage (gross square footage or net square footage) we need the advice/help of a trained aerodynamicist. Of which I am not one

 

[GrauGeist]

One of reasons I like the '190 lite' better
OTOH, the 14R would've been a good match to the Bf 109X.

When you say Bf109X, are you referring to the Bf109F project (Wk.Nmr 5608) fitted with the BMW801A or the earlier Bf109E test project (V21, WkNmr 1770) fitted with a P&W R-1830 engine?

 

[Shortround6]

OTOH, the 14R would've been a good match to the Bf 109X.

The 14R was the equivalent of modern day "vaporware".

In 1946 it was listed as an 1805lb engine, with truly impressive altitude performance (one wonders where the turbocharger was hiding).
It was 91.6% the size of the BMW 801 and it ran about 100rpm slower (96%)
Not sure what a 1415hp (take-off?) radial that is the size/diameter of the BMW 801 gets you? Yes it is lighter than BMW 801 but what does it do over the DB 605 engine?

 

[tomo pauk]

When you say Bf109X, are you referring to the Bf109F project (Wk.Nmr 5608) fitted with the BMW801A or the earlier Bf109E test project (V21, WkNmr 1770) fitted with a P&W R-1830 engine?

Bf 109X was, IMO, a bespoke project. New fuselage, cockpit, canopy, fuel tank and new wing are sorta giveaways.
Ditto for the Bf 109 V21.

The 14R was the equivalent of modern day "vaporware".

In 1946 it was listed as an 1805lb engine, with truly impressive altitude performance (one wonders where the turbocharger was hiding).
It was 91.6% the size of the BMW 801 and it ran about 100rpm slower (96%)
Not sure what a 1415hp (take-off?) radial that is the size/diameter of the BMW 801 gets you? Yes it is lighter than BMW 801 but what does it do over the DB 605 engine?

I was going with the table that Germans compiled during the ww2.

 

[drgondog]

Does that mean that - everything else being equal - the plane with the higher wing loading climbs worse?
I mean if you compare two planes of the same type just with different wing areas. e.g. Fw 190 V1 k and Fw 190 V1 g.
Pls excuse my laymanship.

Misspoke above -The simple equation for ROC is (T*V - D*V)/W

So, in yor example, the lighter of the two FW 190s assuming all else equal, will have a better rate of climb.

Where the W/L comes into play for your example is when parasite drag of the two are equal, but the wing area is different - is that for the same veocity the larger wing/smaller CL in this comparison - has less Induced drag, which influences the above equation.

The devil in the details is that for same airfoil and wing construction, the profile/parasite drag should be lower for the smaller wing area version perhaps offsetting higher Induced drag.

 

[Shortround6]

I was going with the table that Germans compiled during the ww2.

The history of the GR 14R is rather sketchy and contradictory.
Somehow they got one engine into the MB 157 and they got that to fly in 1942 under German supervision. Engine (and cowl?) is removed and sent to Germany, air frame destroyed in Allied bombing raid. Not much is heard about the GR 14R that went to Germany.

The 14R shows up in the 1944 edition of the Aircraft Engines of World. I haven't looked in the 1945 edition, I have it in the 1946 edition with rather different power figures or perhaps I should say same power ratings at rather different heights, also different fuel requirements.

In 1945/46 GR becomes part of SNECMA and the engine is marketed through them and goes through several modifications/improvements. It is listed until at least the 1953 edition but is down to a single speed supercharger.

The real problem is finding what it powered.

Wiki says the French built two Bréguet 500 Colmar twin engine transports during the war, one was destroyed before completion in a bombing raid and the other flew 27 February 1945 and was used by French Air Force as a VIP transport and scrapped in Oct 1947. One other plane showed up, the four engined SNCAC NC.211 Cormoran of which 2 were built and 9 partially completed before program canceled. The 1st prototype crashed on it's first flight which probably didn't help things (unrelated to the engines) July 20th 1948.

There may have been something else. There are sure a lot of engine variations listed on Wiki and in books.
But numbers of engines built, when and actually used ??????