P-40 vs. Yak-1 vs. Hurricane

MiTasol said:

The collapsing problem was primarily a result of the pilot not waiting until the gear was fully locked down mixed with an indication system that was not precise enough (indicated down as opposed to down and locked).

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I imagine a big cause of this being that the Tomahawk took about 45 seconds for its gear to operate whereas the Hurricane and Spitfire were much shorter. I can't find the figures right now but I seem to recall them being closer to 15 seconds.

Pilots used to the British fighters might run into trouble when moving on to P-40s.

EDIT:
Hurricane - raised in 8, lowered in 4.
Spitfire - raised in 10, lowered in 15.

Spitfire had 5ft 8 1/2in of wheel tread/track
Hurricane had 7ft 7in of wheel tread/track
P-40 had 8ft 2 1/2in of wheel tread/track
A P-51 had 11ft 10in of wheel tread/track
AN F4F had 6ft 5in of wheel tread/track

Shortround6 said:

Spitfire had 5ft 8 1/2in of wheel tread/track
Hurricane had 7ft 7in of wheel tread/track
P-40 had 8ft 2 1/2in of wheel tread/track
A P-51 had 11ft 10in of wheel tread/track
AN F4F had 6ft 5in of wheel tread/track

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And the Bf 109 (F for which I have the data to hand) had a track of 2062mm, +/- 40mm, near enough 6'9", roughly a foot MORE than the Spitfire.
There goes another myth. The problem for the 109 was the geometry and the 99 degree angle between axle and oleo strut.
Cheers
Steve

Shortround6 said:

Spitfire had 5ft 8 1/2in of wheel tread/track
Hurricane had 7ft 7in of wheel tread/track
P-40 had 8ft 2 1/2in of wheel tread/track
A P-51 had 11ft 10in of wheel tread/track
AN F4F had 6ft 5in of wheel tread/track

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Impressive set of stats Shortround.
As a comparative, a fighter I always thought had a wide landing gear track was the FW-190.
Could you possibly post that measurement as well, please?


Elvis

If I've read the 'Prufung der Nachspur' diagram in the Fw 190 A-2 to A-6 handbook correctly the track should be 2 x 1750mm, That is 3.5m or about 11'6".
I would be grateful of some confirmation, I'm not 100% sure I have understood the diagram correctly.
Cheers
Steve

Well, there may be two different dimensions, distance between attachment points and distance between tire centers

Looks like the distance between tire centers is NOT greater than the diameter of the propeller but I would check a better source than a drawing

I've posted this bit from the RAE's 109 report before but I think it's always useful:

Landing
This is definitely more difficult than on the Hurricane or Spitfire, mainly owing to the high ground attitude of the aeorplane. The aeroplane must be rotated through a large angle before touch down, and this requires a fair amount of skill on the part of the pilot, and tempts him to do a wheel landing. If a wheel landing is done there is a strong tendency for the left wing to drop just before touch down, and when the ailerons are used quickly to bring the wing up they snatch a little, causing the pilot to over-correct.

Not as snappy as a 'the wheels were narrow' for the History Channel, however ...

It's in the diagram for setting up the toe out of the wheels. If I've read the correct dimension, then the measurement is from the centre of the aircraft to the centre of the wheel at the axle (1750mm), giving an overall track of 3.5m.
The diametre of that propeller disc would be 3.3m? The drawing would have to be accurate as we're debating 100mm on each side
Cheers
Steve

I sure won't debate that distance based on a drawing (and a non-factory one at that).

I'm still not sure I've read the diagram correctly though. Every other reference I've seen so far simply refers to the Fw190's 'wide track undercarriage' without giving a dimension.
Cheers
Steve

Shortround6 said:

Well, there may be two different dimensions, distance between attachment points and distance between tire centers

Looks like the distance between tire centers is NOT greater than the diameter of the propeller but I would check a better source than a drawing

Click to expand...

Thank you for looking into that.
Whichever distance corresponds with the prior figures you gave would be fine.


Elvis

Greyman said:

I've posted this bit from the RAE's 109 report before but I think it's always useful:

Landing
This is definitely more difficult than on the Hurricane or Spitfire, mainly owing to the high ground attitude of the aeorplane. The aeroplane must be rotated through a large angle before touch down, and this requires a fair amount of skill on the part of the pilot, and tempts him to do a wheel landing. If a wheel landing is done there is a strong tendency for the left wing to drop just before touch down, and when the ailerons are used quickly to bring the wing up they snatch a little, causing the pilot to over-correct.

Not as snappy as a 'the wheels were narrow' for the History Channel, however ...

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I suspect every WW2 German pilot would say "Yes of course, but why would you try a wheels landing".

stona said:

I would be grateful of some confirmation, I'm not 100% sure I have understood the diagram correctly.
Cheers
Steve

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That's how I understand it as well Steve.
Lock me in for 3.5m or 11' 6" (Fw190A-5 to A-9, F and G).

Well, to get back ON TOPIC. I have read the whole thread. From what I have read it
seems that pbehn has some good questions and answers, Tomo Pauk also has some
great answers and I believe he was first to ask Clay_Allison one of THE most important
questions, WHEN. Shortround 6 then continued on that theme and ask another one
of THE most important questions WHAT. I am going to assume he was asking " WHAT
do you expect the fighter you need to do?".
January 1938: The Hurricane Mk.I enters RAF service. The other two do not exist in the field.
June 1940: P-40s are delivered. No self sealing fuel tanks & no pilot armor. Hurricane takes
this one even though the P-40s performance is around par at low altitudes with the Spitfire.
February 1941: The first sixty-two Yak-1s are delivered from Plant 301 to the 11 IAP. These
aircraft were built with great scrutiny. The many to follow not so much. By this time the
P-40B comes into play and the RAF has received Mk.II Hurricanes since September 1940.
Even with all this information the questions remain. When and what do you need the aircraft
to do?
Jeff

Dunno how accurate those drawings with the "scale bar" are...

Back on topic didn't last very long, did it?

CORSNING said:

Back on topic didn't last very long, did it?

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Nah, just poor timing - ya beat me by seconds. Carry on....

I think all too often the TV shows go a simple explanation as an accurate one would take so long and be so boring to 90% of the views that they would change the channel or go to the Kitchen for a snack in the middle.

When trying to figure out something like landing and take-off accidents there are a number of things that come into play of which the track of the main wheels may be very minor in good conditions. I am not a pilot so bear with me.

For the 109 you had the strange geometry of the landing gear wheels, the tilt and toe in. Landing into the wind on a good surface (I will get to good surface in a while) this may not be a problem. With a cross wind or less than flat surface? The 3 point landing attitude helped generate lift for a low landing speed? combined with a center of gravity well aft of the wheels allowed for heavy braking without the airplane imitating a roto-tiller.

this allowed for a short landing run and helped keep the pilot from running into things, like other aircraft, fuel trucks etc.
However it takes a good pilot to make his approach fairly level and adopt the 3 point attitude at the last minute.
Adopting the 3 point attitude a bit early gives a miserable view over the nose and may contribute to collisions on the runway/airfield.
Modern 109 pilots seem to go either way,

but that may be what the particular pilot is used to. Please note pilot's head and possible view even with the tail wheel up.
None of these tail draggers had a good view over the nose (F4F and F6F excepted?), more a question of which ones had a less miserable view than others.

Some of these planes were much more likely to ground loop than others. Some had touchier brakes than others. F4Fs were tippy

they sat tall and the landing gear had around 50% more travel than most land planes.
There are probably a number of things I haven't covered but singling out one factor about a plane and blaming a large percentage of it's landing/take off accidents on that one factor is probably wrong.

For most all of these pre-war planes the anticipated landing/take-off surface was grass. However it was hardly "unimproved" any more than a US Pro football field with natural turf is "unimproved" or European champion soccer pitches or polo pitches are "unimproved".
They were filled, rolled and/or tamped with layers of gravel for drainage if the soil required it. In some case while the "landing" field was grass (sod) there were paved taxi ways leading from hangers/terminals to the edges of the flying surface.

Like I said, the real explanation could be very long winded

CORSNING said:

Well, to get back ON TOPIC. I have read the whole thread. From what I have read it.......
January 1938: The Hurricane Mk.I enters RAF service. The other two do not exist in the field.
June 1940: P-40s are delivered. No self sealing fuel tanks & no pilot armor. Hurricane takes
this one even though the P-40s performance is around par at low altitudes with the Spitfire.
February 1941: The first sixty-two Yak-1s are delivered from Plant 301 to the 11 IAP. These
aircraft were built with great scrutiny. The many to follow not so much. By this time the
P-40B comes into play and the RAF has received Mk.II Hurricanes since September 1940.
Even with all this information the questions remain. When and what do you need the aircraft
to do?
Jeff

Click to expand...

And by the late summer of 1941 you have Hurricane IIc with 20mm cannon and bomb racks(?) and production P-40D & E s flying at the factory and the XP-40F with Merlin doing test flights.

To answer Elvis's question, in the Summer of 1941 you have P39D's leaving the factory (since April), the first version with combat equipment. It needs a bigger runway than the Hurricane or P-40 (seldom a problem for the Americans with their unmatched engineering/construction support, for other nations?) and will be a lousier bomber.

The angle is not adjustable via gear legs, but DOES have an adjustment going from the center of the firewall to the front of the gear pivot, so it CAN be set. As far as I know, it is neutral, but I will ask at the museum when I get in there. I have drawings for some of the planes, but not the complete set of Bf 109 drawings.