Hispano Ha.1112 wing

[GregP]

On page 9 of the closed Bf 109F thread, Cimmex posted a pic of the Hispano wing asd said it has 2 spars.

I wanted to correct that, nothing more. In the pic you can see the front "spar" cannot extend through the wheel well and also has enough lightening holes in it to be swiss cheese. It is there only to help steady the cannon mount, not as a spar. It is a local stiffener only.

The strength of the wing is in the normal spar, and it still has only 3 wing mount points to the fuselage.

 

[Shortround6]

OH NO, not the dreaded spar debate

Seriously, thank you. Looking at the picture one can see some (all?) of the attachment points for the "main" spar on the left side of the picture and no visible lugs/ mounting points for the "forward" spar. It might be possible to carry loads around the wheel well with a box type structure but lack of mounting points certainly argues against it. Although the "local" stiffener appears to go from the wheel well to the wing tip? or just short of it?

 

[GregP]

Actually there are the same 3 wing attach points ... one in the rear and a top and bottom in the front. There is no carry-through and this is NOT a spar with any structural potential; it doesn't even make it to the root. As I said, three wing attach points that are exactly in the same place as a German Bf 109.

So ... the Germans COULD have mounted internal wing armament if they had only decided to DO it.

This is NOT a knowck on the Germans and says nothing about the Hispano other than it has the same spar setup as the 109.

 

[Tante Ju]

Actually its a box spar, the main kiad bearing element is the entire wing, with the very thick skin, made of large single metal plates, forming a one big torsion box.

The Bf 109E did mount an internal cannon in the wing, or alternatevly an MG in the other gun bay of the wing. Mounting both was not possible because of ammo drum of the MG FF.

The Bf 109K had similar wing as the F-G, but they did try and test an internal MG 151 / MK 108 inside the wing, mounted in the leading edge foreard of the spar and much of barrel protounding. So internal mounting was entirely possible, but u were restricted to the section between the LE slats and the wheel bay/radiator.

 

[GregP]

But the attach points are connected only to the main spar (upper and lower) and the point at the rear, which is where ALL the flight loads are transferred. So, the entire load comes through the spars to the fuselage mounts. I'm sure some is carried in the wings internally by the skins, but is NOT transferred by them at all.

The fillets are NOT structural in any way and the palne could fly just fine without them. Would be slower, but no weaker.

 

[Shortround6]

Again it comes down to what somebody calls a spar. The P-40 has been described as having both 5 spars and 7 spars. Only the first 3 (?) go wing tip to wing tip (P-40 fuselage sits on top of the wing, the wing is not attached to each side of the fuselage)

The rear "two" spars are not continuous and have "breaks" or zig zags in the area where the ailerons and flaps meet. So are they long spars with zig zags (5 spar wing) or are there two short spars in front of the flaps and two short spars in front of the ailerons for 7 spars?

 

[GregP]

As I said, there are 3 connection points to the fuselage ... which is where ALL the flight loads are transferred.

In a fixed-wing aircraft, the spar is often the main structural member of the wing, running spanwise at right angles (or thereabouts depending on wing sweep) to the fuselage. The spar carries flight loads and the weight of the wings while on the ground. That is a definition. The only place the loads are carried in the Hispano (and German Bf 109) on the ground and in flight is the main spar and the rear attach point in the rear center of the root rib. The rear point is there mostly to carry torsion bending loads, not the main g-loads, which are carried only through the main spar.

If you doubt that, see some Bf 109 combat loss films (Allied gun camera film). When a main spar attach point is hit the wing departs upward or downward. When the rear attach point fails, the wing twists off in a spinning motion before it fails upward or downward.

Good enough to meet the definition and agrees with combat wing camera film.

 

[cimmex]

I will not jump in a new debate but you can built up your own opinion.
Here are some links to the excellent page of Matthias Dorst who is webmaster at meiermotors in Germany with pictures of the Buchon wing and one of an original Bf 109 E-1 so you can see the difference of the construction.
MeierMotors
Messerschmitt Bf109 G-4 (HA WkNr133)
Messerschmitt Bf109E 6-88
cimmex

 

[GregP]

Thanks Cimmex. I don't say the wings are the same, but the thing that looks like a front spar isn't a load-bearing member. But it IS there and is there to help hold the wing guns in place. Doesn't go through to the root rib.

Since the wing attach points are the same, the loads are transmitted via the same attach points as a German Bf 109. I can get pics this weekend. The Spanish wing also had fuel tanks outboard that we removed. This IS an airshow aircraft and won't need to fly long missions.

Other than the wing armament, the wings are VERY close with identical slats, flaps, radiators, cooling gills, etc. The flaps and ailerons are EXACTLY the same and are interchangeable to a large degree, We HAVE put Bf 109 ailerons on and they fit just fine. Haven't tried the flaps yet since ours are fine. I can't tell the difference in the wing profiles and I have pics of both from very close up. That doesn't mean they aren't different airfoils, but it DOES mean they are VERY close.

The Bf 109G-2 (the model the Ha1112 is based on) used an NACA 2R1 14.2 airfoil at the root and an NACA 2R1 11.35 at the tip. The Hispano Ha.1112 used an NACA 2R1 14.2 airfoil at the root and an NACA 2R1 11.35 at the tip. Not much to discern them is it? The internal structure and wing armament have NOTHING whatsoever to do with the airfoils, which are identical, as are the slats and the wing span and area.

That makes them pretty close to kissing cousins in my book. The engines are a slight bit different (tongue in cheek) as are the props. The high-speed performance and max climb won't tell you that, though. Low speed, the Bf 109 was better, particularly in the F and earlier models.

 

[jim]

Mr GreqP

Do you know ,aproximately, what capacity the wing tanks of your spanish 109 had?
And it had them in addition of the internal wing guns?
Thanks you for sharing your informations

 

[GregP]

We removed the tanks (Still have them) but did not measure the capacity. I'm sure I can find out, though.

Yas, they were in addition to the standard fuselage tank under and behind the pilot's seat.

 

[Tante Ju]

Other than the wing armament, the wings are VERY close with identical slats, flaps, radiators, cooling gills, etc. The flaps and ailerons are EXACTLY the same and are interchangeable to a large degree, We HAVE put Bf 109 ailerons on and they fit just fine. Haven't tried the flaps yet since ours are fine. I can't tell the difference in the wing profiles and I have pics of both from very close up. That doesn't mean they aren't different airfoils, but it DOES mean they are VERY close.

The Bf 109G-2 (the model the Ha1112 is based on) used an NACA 2R1 14.2 airfoil at the root and an NACA 2R1 11.35 at the tip. The Hispano Ha.1112 used an NACA 2R1 14.2 airfoil at the root and an NACA 2R1 11.35 at the tip. Not much to discern them is it? The internal structure and wing armament have NOTHING whatsoever to do with the airfoils, which are identical, as are the slats and the wing span and area.

AFAIK the Spanish received a number of Bf 109G airframes, but sans engines. So the airframe was German manufactured to my best knowledge.. the Spanish may have modded it for their own needs, and to fit some engine they could lay their hands on (there is not much use of an engineless fighter, is there?) but basically its a 109, so it should be largely identical to another 109. No surprise there...

 

[GregP]

From what I have the Spanish managed to get 25 Bf 109G-2 airframes from Germany, minus their tails, and about half of the necessary drawings. They put in the 1,300 hp Hispano-Suiza 12Z-89 engine and flew one as the Hispano Ha.1109. The other 24 airframes aslo got Hiso engines but never became operational.

The Ha.1112-K1L appeared in 1951 with the Hispano-Suiza 12Z-17 engine and became the Tripala. 65 were built.

The final version was the Ha.1112-M1L Buchon with a Rolls-Royce Merlin 500-45 and a 4-bladed prop. They built 172 Buchons.

We have one in restoration now at the Planes of Fame Museum in Chino, California, USA. It appeared in the 2000 film "Pearl Harbor" (lousy movie but great aircraft scenes) in which it played "the Luftwaffe," and was damaged on takeoff when the right brake line burst and failed. Once a slight left swing developed that could not be stopped by right rudder, the groundloop was inevitable. The damage has been repaired and we are now working on the rest of the systems, cables, hydraulic and coolant lines, etc. that require attention.

Once the airframe is ready, the Merlin will have to be disassembled and looked at since it suffered a prop strike. It is thought the possible damage will be slight since the engine was being shut down as the plane groundlooped. We are well along with it and are now at a place where the most important driver of the schedule is money.

Unfortunately (as far as I'm concerned) the intent is to mimic a Bf 109, so we will be fitting a 3-bladed prop made from a cut-down DC-3 propeller, and will be painting it in some German scheme. The aircraft is not in demand on the airshow circuit so it will probably be made into a movie plane to represent a Bf 109. The airframe is being restored stock, though we DID remove the outer wing fuel tanks as I said earlier. So ... it COULD be fitted with a 4-blade prop as a Buchon anytime. From the firewall back it is pure Messerschmitt Bf 109G-2, fitted with a new engine mount, Merlin, and a new cowling that covers the Merlin. We have covered over the wing gun ports, so this one will NOT have any noticeable exterior gun openings as far as I know.

It could easily be fitted with a fake cannon through the spinner, though. All it takes is a spinner with something that looks like a cannon barrel on the end of the spinner. Balancing that might not be easy, so it may be just a hole in the spinner.

 

[Tante Ju]

I stand corrected. So, the Spanish set up a proper production line based on drawings etc? Or it was all "hand built" in small shops?

 

[GregP]

Don't really know, but we have one and can get parts that sometimes take a year to find. The engine mount came rapidly, so it IS available. The rest we pretty much fabricate.

 

[razor1uk]

I think when 'production line' is stated, we have to imagine something more akin to a low volume, non conveyor style more in-fitting to older methods, like a machinery-lesser version to what Messershmitt and most manufacturers used prior to the 40's, i.e; planes (fuselage separate to wings) built up in position, on jigs and stands.