Copying advances

[GregP]

OK, I looked at a very detailed cutaway and it looks like the Me 262 has 6 slat tracks per side. The F-86 has eight, 2 for each of the four slats and no two have the same part number. But the slat tracks DO look very similar. From the diagram I can't tell if the chord and travel are similar. The slats do not appear to be the same chord but might well run on similar but not the same tracks, since the F-86 tracks are not all placed in the same area.

There MIGHT be one or two with the same profile, but I seriously doubt it since the airfoils were not the same.

The F-86 used an NACA 0009-64 at the root and an NACA 0008.1-64 at the tip while the Me 262 used an NACA 00011-0.825-35 at the root and an NACA 00009-1.1-40 at the tip. Of necessity the slats would not have the same profile, though it could be admittedly close to the naked eye unless one were laid on top of the other.

Seriously there are different part numbers for each F-86 slat as the airfoil changes from root to tip.

Right now I'm having a devil of a time finding slat bearings to continue with the F-86 leading edges I was doing for Steve Hinton. They're out there somewhere, but finding them is proving problematic. It would be very interesting to see an Me 262 slat track since I have a complete set of F-86F slat tracks right at this time, just waiting for bearings, and am very familiar with them just now.

Unfortunately, the Me 262 we USED to have is now in Paul Allen's collection, so I have no access.

So, Joe might be right about one or two slats, but certainly not for a set. It would be interesting to find out by looking at both side by side.

 

[Reegor]

A big missed opportunity was Axis copying of American standard procedure flying methods, such as checklists. I'm sure captured checklists and manuals fell into German hands quickly; they were even discussed in Life magazine. The Germans had terrible problems with training casualties and inadequate training time (due to lack of fuel, mainly), and those problems would have been appreciably helped by the American training and flying methods.

However, the Germans were not interested in this American innovation. In fact, they remained quite undisciplined as pilots up through the end of the war. (Wolfgang Schmidt, unpublished PhD dissertation.) That worked fine for the experienced ones, but there were few of them flying by mid 1944.
IDK for sure, but I gather the same was true for Japan.

 

[GrauGeist]

The Luftwaffe was undiscliplined?

You do realize that the Luftwaffe had one of the most extensive flight schools of most militaries of the world, right?

Only after conditions became desperate, were the training standards lowered considerably.

Not sure where you're getting your info from, but it's missing the mark by quite a ways...

 

[beitou]

The check list seems such an obvious thing now. What did the Germans do, trust preflight checks and others to memory, rote learning, I can't imagine what else they used?

 

[parsifal]

ive never heard the germans were undisciplined in flight techniques. They did suffer higher rates of non-combat related attrition, but thats usually put down to the operating conditions they were forced into (East Front etc) and the intense level of operations they were often thrust into. it just doesnt ring true that they were undisciplined, and as a consequence suffered heavier losses......

 

[BiffF15]

In Gunther Ralls book he speaks about checklists and how the Americans used them so heavily. If I remember correctly he liked after getting used to it. He doesn't speak of or to German procedures / checklists specifically.

Cheers,
Biff

 

[Koopernic]

OK, I looked at a very detailed cutaway and it looks like the Me 262 has 6 slat tracks per side. The F-86 has eight, 2 for each of the four slats and no two have the same part number. But the slat tracks DO look very similar. From the diagram I can't tell if the chord and travel are similar. The slats do not appear to be the same chord but might well run on similar but not the same tracks, since the F-86 tracks are not all placed in the same area.

There MIGHT be one or two with the same profile, but I seriously doubt it since the airfoils were not the same.

The F-86 used an NACA 0009-64 at the root and an NACA 0008.1-64 at the tip while the Me 262 used an NACA 00011-0.825-35 at the root and an NACA 00009-1.1-40 at the tip. Of necessity the slats would not have the same profile, though it could be admittedly close to the naked eye unless one were laid on top of the other.

Seriously there are different part numbers for each F-86 slat as the airfoil changes from root to tip.

Right now I'm having a devil of a time finding slat bearings to continue with the F-86 leading edges I was doing for Steve Hinton. They're out there somewhere, but finding them is proving problematic. It would be very interesting to see an Me 262 slat track since I have a complete set of F-86F slat tracks right at this time, just waiting for bearings, and am very familiar with them just now.

Unfortunately, the Me 262 we USED to have is now in Paul Allen's collection, so I have no access.

So, Joe might be right about one or two slats, but certainly not for a set. It would be interesting to find out by looking at both side by side.

The claim is that the the first 7 F-86 prototypes used actual Me 262 slat hardware comes from this article by by Larry Davis "Sabre Jet
XP-86 SWEPT WING DEVELOPMENT" http://sabre-pilots.org/classics/v53sabre.htm

Larry Davis has 38 books on Aviation listed on Amazon, most on US types such as the Sabre so he seems highly plausible source to me.

The actual quote from his article is "Slowly but surely, North American's engineers brought the design to its final shape. But the slat design remained a problem. Finally, an entire Me-262 wing was flown in from Wright Field. North American's engineers disassembled the slats and modified the slat track mechanism to fit the XP-86 wing, using the Me-262 slat lock and control switch. Although not perfect, it was a start and the slat worked. In fact, the first seven aircraft used Me-262 slat locks and tracks. "

The wing section of the F-86 was not however based on that of the Me 262. The 6 digit airfoil used on the Sabre was a refinement of the laminar flow type used by North American on the P-51 which had superb high speed characteristics. The Me 262 wing section was a proper high speed section suitable for supersonic use at an appropriate angle but it was still not as advanced as that of the P-51 series. The main thing was that the 6 digit airfoils offered large internal volume for a strong stiff structure and fuel. The Germans incidentally flew Laminar Flow wings on the Me 309 in Jun 1942, it was all their own work.

Adolf Bussmann published an article on wing sweep on an airfoil at supersonic speed in 1933. It was no secret at the time and actually revealed to American researchers who simply forgot it. Low key research continued but in 1940 a very major German effort started. One of the problems of swept wings is their handling at low speed or rather high angles of attack. For one a property called spanwise flow leads to premature wing tip stall, the other is a that although they have a greatly higher stall angle this comes at a disproportionately greater increase in drag that can be so high that aircraft engine is overpowered and the aircraft falls out of the sky. This can lead to something called "Sabre Dance", it effected the F-100 super sabre and there is a pretty horrific video of it on you tube.

The Germans naturally researched for solutions. One of these was the slat. It is no surprise that NA engineers might have copied some elements of the German slat mechanism, slat engineering is very finicky and these men had no time to waste: the cold war had started and they had competition from Republic, Lockheed and Grumman.

The only US aircraft I know of that used slats were Northrop's flying wings which used power (rather than automatic slats) as part of the auto-stable design.

The other solutions the Germans looked into was the nose flap (also called leading edge flap), the krueger flap. These two leading edge devices are entirely German in development. Another two was the scimitar or crescent wing (seen on the Handley Page Victor but conceived of for a swept wing version of the Arado Ar 234), the forward swept wing (test beded on the Ju 287). A very subtle one was called "aerodynamic twist" where the outer wing was given a blunter profile that would stall later.

Most of the German "secret projects" used these technologies. The book "secret Messerschmidt projects" references most of these. A type of area ruling where the aircraft fuselage is 'waisted' in at the wing so as to reduce span-wise flow across the wing was also found to help conform to the area rule, which had been discovered at Junkers.

From the F-86-30F onwards the slats were abandoned, the wing profile changed by adding different leading edges and wing fences were added at 70% of span, similar to the MiG 15. The F-100 Super Sabre used leading edge flaps.

The Germans were aware of wing fences as well and explored variable sweep. I haven't seen any awareness of dog tooth leading edges or vortilons.

In 1948 American engineers were still digesting the masses of captured German aerodynamic data, there was about 2 years worth.

 

[GrauGeist]

Davis' statement implies first, that a complete wing of a Me262 was "flown in" and parted out for the slat mechanism and then goes on to say that the first seven F-86 models had complete Me262 slat assemblies.

So, where did they get the other six Me262s from, then?

Just because Davis has authored a number of books doesn't make him an authority on the subject.

Performance requirements were met by incorporating a 35° swept-back wing, using NACA 4-digit modified airfoils, using NACA 0009.5–64 at the root and NACA 0008.5–64 at the tip,[9] with an automatic slat design based on that of the Messerschmitt Me 262 and an electrically adjustable stabilizer, another feature of the Me 262A.
Mac Blair: "Evolution of the F-86" AIAA Evolution of Aircraft Wing Design Symposium, 18 March 1980
Radinger and Schick 1996
Willy and Schick 1996

There has been several instances over the years where facts were "embellished" in a publication and then later authors picked the information up and used that information in their publications. The epic saga of the mystery Ju390 flight to North America comes to mind...

To just stuff a Me262 slat into the F-86 seems wonderful and a little bit Hollywood, but the reality is that the slats were designed for the Me262's wing, not the F-86. It was designed for a certain speed/weight/stall and had specific dimensions. Now unless the F-86 had the EXACT same flight characteristics as the Me262, then there would be some serious math involved to ensure that the aircraft and the test pilot were not going to be in harm's way when this first flew.

Taking captured technology and arbitrarily sticking it onto a new airframe is not as easy as going out to the garage and taking a wheel off of your Datsun and bolting it onto your Chevrolet.

On another note: "The only US aircraft I know of that used slats were Northrop's flying wings which used power (rather than automatic slats) as part of the auto-stable design."
Curtiss was working with leading-edge slats in the late 1920's...

 

[FLYBOYJ]

I'm going to flat out say with regards to this Me 262 slat claim, Mr. Davis either had an editing slip up, brain fart, is delusional or on drugs!!!

There is no way in hell that any manufactuer would have sanctioned a foreign made component to be placed on a production aircraft, ESPECIALLY a state of the art aircraft (at the time) like an F-86. Even during WW2, there were processes in place where a design had to be approved (usually by representatives of engineering, production, and quality assurance), that's including the material the component is made from as well as the processing (heat treating, surface finishing, etc.). Who do you think "would have" taken responsibility for this component, not knowing what material it was made from or not knowing if it was even manufactured properly???? What if the part wasn't properly heat treated or over temped during heat treatment so it would fail??? (There was a lot of sabotage well documented during -262 production).

No engineer and/ or Quality Assurance Manager would approve this, not then, not now. That's not to say they fitted components to the prototype aircraft, went back into a machine shop and reversed engineered the assembly, and USED THE -262 DESIGN ON THE FIRST 7 P-86s!!! I'm hoping THAT'S what Mr. Davis meant to say!!!!

Mr. Davis may have wrote 9 aviation books, some of them pretty neat, but I don't know his background or know if he ever worked on or flown a REAL aircraft (Many so-called aviation experts who make statements like this usually turn out to be armchair generals). If someone is to make a claim like this, they better have some strong evidence to back it up!!!!

I've been in aviation for 36 years and have worked for manufacturers (Lockheed, Boeing, Rohr, Sikorsky, and as a contractor for Northrop to name a few) and I'll tell you based on experience and having the opportunity to work with many WW2 era mechanics, unless this was part of an R&D program (and even then I would have doubts), no one in their right mind would sanction this – now or in 1945!!!!!

OK, I looked at a very detailed cutaway and it looks like the Me 262 has 6 slat tracks per side. The F-86 has eight, 2 for each of the four slats and no two have the same part number. But the slat tracks DO look very similar. From the diagram I can't tell if the chord and travel are similar. The slats do not appear to be the same chord but might well run on similar but not the same tracks, since the F-86 tracks are not all placed in the same area.

There MIGHT be one or two with the same profile, but I seriously doubt it since the airfoils were not the same.

The F-86 used an NACA 0009-64 at the root and an NACA 0008.1-64 at the tip while the Me 262 used an NACA 00011-0.825-35 at the root and an NACA 00009-1.1-40 at the tip. Of necessity the slats would not have the same profile, though it could be admittedly close to the naked eye unless one were laid on top of the other.

Seriously there are different part numbers for each F-86 slat as the airfoil changes from root to tip.

Right now I'm having a devil of a time finding slat bearings to continue with the F-86 leading edges I was doing for Steve Hinton. They're out there somewhere, but finding them is proving problematic. It would be very interesting to see an Me 262 slat track since I have a complete set of F-86F slat tracks right at this time, just waiting for bearings, and am very familiar with them just now.

Unfortunately, the Me 262 we USED to have is now in Paul Allen's collection, so I have no access.

So, Joe might be right about one or two slats, but certainly not for a set. It would be interesting to find out by looking at both side by side.

Next month I'll be in California and if all goes well, Stead in June. I should be coming across an F-86 while there, if I get a chance I'll try to take some pics of the slats (If the aircraft I come across has them).

BTW - I e mailed the webmaster from the site that printed Larry Davis' article, e mail address expired...

Looked up Larry Davis - authored several books on aircraft and drag racing - was a fire fighter by trade.

 

[tomo pauk]

...

On another note: "The only US aircraft I know of that used slats were Northrop's flying wings which used power (rather than automatic slats) as part of the auto-stable design."
Curtiss was working with leading-edge slats in the late 1920's...

The Curtiss SBC-2 have had those in service in 1944.

 

[GrauGeist]

...The only US aircraft I know of that used slats were Northrop's flying wings which used power (rather than automatic slats) as part of the auto-stable design...

On another note: "The only US aircraft I know of that used slats were Northrop's flying wings which used power (rather than automatic slats) as part of the auto-stable design."
Curtiss was working with leading-edge slats in the late 1920's...

The Curtiss SBC-2 have had those in service in 1944.

Exactly. Curtiss (among others) had been working with that technology many years before WWII. Slats in an American designed aircraft (even post-WWII) shouldn't come as any surprise.

 

[FLYBOYJ]

I've been in touch with Mr. Davis - He claims two former NA employees stated that the first XP-86 had -262 parts installed during it's first flight. More to come...

 

[awack]

I've been in touch with Mr. Davis - He claims two former NA employees stated that the first XP-86 had -262 parts installed during it's first flight. More to come...

Oh heck yes!!! cant wait...any thing about the me 262 has my interest.