More long-range Spitfires and daylight Bomber Command raids, with added nationalistic abuse (was: #1 Jet of World War II)

In article , Guy Alcala
writes
Dave Eadsforth wrote:

snip

To enlarge on my 'thick wing section' description, and working from
memory of a book read long ago (which can be fatal), I recall that Davis
conceived of a wing section that was based on a mathematically deformed
circle, which he believed would give a more laminar flow. The thicker,
'teardrop-shaped' aerofoil section that resulted was also very useful
structurally, given that he wanted to combine it with a high aspect
ratio wing.

Of course, any wing section inboard of the engines was going to have its
airflow messed up considerably by a few minor essentials; like engine
nacelles and de-icing boots etc etc, but the wing outboard of the
engines may have performed as Davis believed it should during cruise.

snip

He was quite irritated that Consolidated didn't provide full covers for the
main
gear wheel wells, as he felt that defeated much of the drag reduction.

Guy

Some penny-pinching accountant at work perhaps?

I was always mystified by the fact that the Spitfire didn't get full
wheel-well covers until late in the war - they went to all that trouble
gluing split peas all over the wing to optimise the placement of flush
and round headed rivets and missed out on some thing that seems even
more obvious (unless the drag from the wheel well really was
inconsequential up to speeds of 400 mph or so - but that seems a bit
counter instinctive).

Cheers,

Dave

--
Dave Eadsforth

In article , Dave Eadsforth
writes
Some penny-pinching accountant at work perhaps?

I was always mystified by the fact that the Spitfire didn't get full
wheel-well covers until late in the war - they went to all that trouble
gluing split peas all over the wing to optimise the placement of flush
and round headed rivets and missed out on some thing that seems even
more obvious (unless the drag from the wheel well really was
inconsequential up to speeds of 400 mph or so - but that seems a bit
counter instinctive).

I think originally it simplified the gear retraction 'hydraulics'. The
first Spits had a hand pump to retract the gear, which required IIRC 27
pumps to fully retract it. I guess the full wheel well covers probably
came along with the retractable tail wheel (possibly more important?) as
well?

--
John

John Halliwell wrote:

In article , Dave Eadsforth
writes
Some penny-pinching accountant at work perhaps?

I was always mystified by the fact that the Spitfire didn't get full
wheel-well covers until late in the war - they went to all that trouble
gluing split peas all over the wing to optimise the placement of flush
and round headed rivets and missed out on some thing that seems even
more obvious (unless the drag from the wheel well really was
inconsequential up to speeds of 400 mph or so - but that seems a bit
counter instinctive).

I think originally it simplified the gear retraction 'hydraulics'. The
first Spits had a hand pump to retract the gear, which required IIRC 27
pumps to fully retract it. I guess the full wheel well covers probably
came along with the retractable tail wheel (possibly more important?) as
well?

No, they were removed to simplify things at RAF suggestion in spec. F.16/36,
dated 28 July 1936, which entailed the changes to be made from the
prototype. F.16/36 was the spec for the first production contract (on 3
June 1936) for 310 a/c, which lists thirty-three seperate paragraphs, each
entailing one change:

Para xxi: "Provided no reduction in the performance will be entailed, the
hinged flaps on the wheels may be replaced by fixed flaps which, when
retracted, will not cover the wing apertures completely." Presumably no
significant reduction in performance resulted, at least not at the speed the
a/c was then capable of attaining.

Guy

In article , Guy Alcala
writes
John Halliwell wrote:

In article , Dave Eadsforth
writes
Some penny-pinching accountant at work perhaps?

I was always mystified by the fact that the Spitfire didn't get full
wheel-well covers until late in the war - they went to all that trouble
gluing split peas all over the wing to optimise the placement of flush
and round headed rivets and missed out on some thing that seems even
more obvious (unless the drag from the wheel well really was
inconsequential up to speeds of 400 mph or so - but that seems a bit
counter instinctive).

I think originally it simplified the gear retraction 'hydraulics'. The
first Spits had a hand pump to retract the gear, which required IIRC 27
pumps to fully retract it. I guess the full wheel well covers probably
came along with the retractable tail wheel (possibly more important?) as
well?

No, they were removed to simplify things at RAF suggestion in spec. F.16/36,
dated 28 July 1936, which entailed the changes to be made from the
prototype. F.16/36 was the spec for the first production contract (on 3
June 1936) for 310 a/c, which lists thirty-three seperate paragraphs, each
entailing one change:

Para xxi: "Provided no reduction in the performance will be entailed, the
hinged flaps on the wheels may be replaced by fixed flaps which, when
retracted, will not cover the wing apertures completely." Presumably no
significant reduction in performance resulted, at least not at the speed the
a/c was then capable of attaining.

Guy


Thanks for that quote - ends a long-standing mystery!

Perhaps they should have stuck with that nice streamlined tailskid...

Cheers,

Dave

--
Dave Eadsforth

Dave Eadsforth wrote:

In article , Guy Alcala
writes
John Halliwell wrote:

In article , Dave Eadsforth
writes
Some penny-pinching accountant at work perhaps?

I was always mystified by the fact that the Spitfire didn't get full
wheel-well covers until late in the war - they went to all that trouble
gluing split peas all over the wing to optimise the placement of flush
and round headed rivets and missed out on some thing that seems even
more obvious (unless the drag from the wheel well really was
inconsequential up to speeds of 400 mph or so - but that seems a bit
counter instinctive).

I think originally it simplified the gear retraction 'hydraulics'. The
first Spits had a hand pump to retract the gear, which required IIRC 27
pumps to fully retract it. I guess the full wheel well covers probably
came along with the retractable tail wheel (possibly more important?) as
well?

No, they were removed to simplify things at RAF suggestion in spec. F.16/36,
dated 28 July 1936, which entailed the changes to be made from the
prototype. F.16/36 was the spec for the first production contract (on 3
June 1936) for 310 a/c, which lists thirty-three seperate paragraphs, each
entailing one change:

Para xxi: "Provided no reduction in the performance will be entailed, the
hinged flaps on the wheels may be replaced by fixed flaps which, when
retracted, will not cover the wing apertures completely." Presumably no
significant reduction in performance resulted, at least not at the speed the
a/c was then capable of attaining.

Guy


Thanks for that quote - ends a long-standing mystery!

Perhaps they should have stuck with that nice streamlined tailskid...

I just last night got in Price's "The Spitfire Story" at my library, which I
devoured immediately. Aside from confirming the above (that there was no
noticeable change in performance with the wheel flaps removed from the
prototype), he also says that Mitchell wanted to stick with the tailskid, but the
Air Ministry insisted on the tailwheel, because they knew (but couldn't tell
Mitchell at the time, because it was classified) that they were going to lay down
all-weather (i.e. paved) runways at all the fighter bases, and the tail skid
wouldn't last long under those conditions. This thing's just filled with great
info.

Guy

Subject: More long-range Spitfires and daylight Bomber Command raids,
with
From: Guy Alcala

he also says that Mitchell wanted to stick with the tailskid, but the
Air Ministry insisted on the tailwheel, because they knew (but couldn't tell
Mitchell at the time, because it was classified) that they were going to lay
down
all-weather (i.e. paved) runways at all the fighter bases, and the tail skid
wouldn't last long under those conditions. This thing's just filled with
great
info.

Guy


It seems as though the Air Ministry didn't entirely trust Mitchell. Imagine
being an aircraft designer and having th air ministry withhold info that would
impact on your designs. The mind boggles.


Arthur Kramer
344th BG 494th BS
England, France, Belgium, Holland, Germany
Visit my WW II B-26 website at:
http://www.coastcomp.com/artkramer

ArtKramr wrote:

Subject: More long-range Spitfires and daylight Bomber Command raids,
with
From: Guy Alcala

he also says that Mitchell wanted to stick with the tailskid, but the
Air Ministry insisted on the tailwheel, because they knew (but couldn't tell
Mitchell at the time, because it was classified) that they were going to lay
down
all-weather (i.e. paved) runways at all the fighter bases, and the tail skid
wouldn't last long under those conditions. This thing's just filled with
great
info.

Guy


It seems as though the Air Ministry didn't entirely trust Mitchell. Imagine
being an aircraft designer and having th air ministry withhold info that would
impact on your designs. The mind boggles.

It wasn't a case of trust, just a case of need to know. Mitchell only needed to
know that a tailwheel was a firm requirement, not the rationale behind it, to
design one. I imagine the spec change to increase the armament from 4 to 6 or 8 x
..303s was handled the same way -- they told him what they wanted and asked him if
it could be done, but probably not the reasoning behind it. Whether the tailwheel
case was an example of the government being classification happy is another
matter; the Brits tended to be (and still are, to a great extent) a lot more
reluctant about releasing such details, even when they're apparently innocuous,
than we were/are. OTOH, there were some probably unnecessary security concerns
over Mitchell's technical assistant, S/Ldr H.J. 'Agony' Payn, AFC RAF (ret)
because he'd divorced and his second wife was foreign (maybe German; I forget).
After Mitchell died he was named manager of the Design Department at Supermarine
(not Chief Designer, the post which Mitchell had held). The Air Ministry forced
Supermarine to remove him from work on the Spitfire or anything else classified
because of this, and in fact the company fired him.

Supermarine tried two different designs, a single wheel and one with dual wheels
(side by side). The latter tended to get clogged with mud, so they went with the
single.

Guy