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Kyle Boatright
April 5th 07, 02:17 AM
Those of us who fly behind (or in front of) wooden props usually reduce RPM
significantly when entering rain. I reduce RPM to <1900 in rain, or I see
minor damage, despite the urethane leading edges. For me, 1900 rpm results
in a rotational tip speed of about 400 mph. This doesn't consider the
forward motion of the aircraft.

In WWII, more than a few combat aircraft used wooden propellers - Spitfires,
Hurricanes, and Me-109's being high profile examples. However, I have never
heard of any rain/prop issues with those aircraft. And I'm sure there were
plenty of occasions where those aircraft were flown full-out in rain. FYI,
with the Spit/merlin combination, the prop is geared to roughly half the
engine speed of 3,000 RPM. At 1500 prop rpm, a 10.75' diameter prop has a
tip speed of roughly 575 mph.

That's the kind of tip speed that will supposedly wreck a wooden prop in the
rain. So, what was different about those props? Were the blades
essentially disposable and nobody gave a second thought to trashing a set?
Did the blades incorporate some sort of technology that I've missed? (Brass
leading edges don't count - to the best of my knowledge, Spits didn't have
'em.)

Thoughts?

KB

Rich S.[_1_]
April 5th 07, 05:32 AM
"Kyle Boatright" > wrote in message
. ..
>
> Were the blades essentially disposable and nobody gave a second thought to
> trashing a set?

"Scotty, give me warp 9!"

"Aye, Cap'n, but she's gonna blow . . ."

"It won't matter. If that Klingon ship gets through our rear deflectors with
a disruptor blast, we'll all be dead!"

Rich S. :)
(I've never shipped out aboard the ikvamar, nor do I play one on tv.)

Montblack
April 5th 07, 08:20 AM
("Rich S." wrote)
> "It won't matter. If that Klingon ship gets through our rear deflectors
> with a disruptor blast, we'll all be dead!"


You want to go with your Romulans in this situation.

1. Beam aboard the other vessel - being careful not to jeopardize said
vessel's W&B
2. Remove their (P)ulse (R)eflective (O)ptics (P)rototype (PROP)
3. Beam back to your craft
4. Hope the backing plate holes line up
5. Quickly install aforementioned alien technology (PROP)
6. Remove your fake ears
7 Off you go...


MontBlack-Kite-Class-Cruiser
http://legacy.filefront.com/screenshots/File/76934/1

JP[_1_]
April 5th 07, 08:54 AM
"Kyle Boatright" > wrote in
om...
>
> Those of us who fly behind (or in front of) wooden props usually reduce
> RPM significantly when entering rain. I reduce RPM to <1900 in rain, or I
> see minor damage, despite the urethane leading edges. For me, 1900 rpm
> results in a rotational tip speed of about 400 mph. This doesn't consider
> the forward motion of the aircraft.
>
> In WWII, more than a few combat aircraft used wooden propellers -
> Spitfires, Hurricanes, and Me-109's being high profile examples. However,
> I have never heard of any rain/prop issues with those aircraft. And I'm
> sure there were plenty of occasions where those aircraft were flown
> full-out in rain. FYI, with the Spit/merlin combination, the prop is
> geared to roughly half the engine speed of 3,000 RPM. At 1500 prop rpm, a
> 10.75' diameter prop has a tip speed of roughly 575 mph.
>
> That's the kind of tip speed that will supposedly wreck a wooden prop in
> the rain. So, what was different about those props? Were the blades
> essentially disposable and nobody gave a second thought to trashing a set?
> Did the blades incorporate some sort of technology that I've missed?
> (Brass leading edges don't count - to the best of my knowledge, Spits
> didn't have 'em.)
>
> Thoughts?
>
> KB


Many prewar (WWII) fighters used wooden propellers. During the war the
British fighters like Spitfires and Hurricanes as well as German Me-109's
and FW-190's were equipped with metal blade propellers. This can be seen in
e.g. photographs presenting downed planes. The bent blades are often clearly
visible.

JP

Kyle Boatright
April 5th 07, 11:44 AM
"JP" > wrote in message
...
>
> "Kyle Boatright" > wrote in
> om...
>>
>> Those of us who fly behind (or in front of) wooden props usually reduce
>> RPM significantly when entering rain. I reduce RPM to <1900 in rain, or
>> I see minor damage, despite the urethane leading edges. For me, 1900 rpm
>> results in a rotational tip speed of about 400 mph. This doesn't consider
>> the forward motion of the aircraft.
>>
>> In WWII, more than a few combat aircraft used wooden propellers -
>> Spitfires, Hurricanes, and Me-109's being high profile examples.
>> However, I have never heard of any rain/prop issues with those aircraft.
>> And I'm sure there were plenty of occasions where those aircraft were
>> flown full-out in rain. FYI, with the Spit/merlin combination, the prop
>> is geared to roughly half the engine speed of 3,000 RPM. At 1500 prop
>> rpm, a 10.75' diameter prop has a tip speed of roughly 575 mph.
>>
>> That's the kind of tip speed that will supposedly wreck a wooden prop in
>> the rain. So, what was different about those props? Were the blades
>> essentially disposable and nobody gave a second thought to trashing a
>> set? Did the blades incorporate some sort of technology that I've missed?
>> (Brass leading edges don't count - to the best of my knowledge, Spits
>> didn't have 'em.)
>>
>> Thoughts?
>>
>> KB
>
>
> Many prewar (WWII) fighters used wooden propellers. During the war the
> British fighters like Spitfires and Hurricanes as well as German Me-109's
> and FW-190's were equipped with metal blade propellers. This can be seen
> in e.g. photographs presenting downed planes. The bent blades are often
> clearly visible.
>
> JP

At one time or another, all of those aircraft flew behind wooden props. Do
a google search for "Wood Rotol propeller spitfire", for example.

KB

JP[_1_]
April 5th 07, 12:40 PM
"Kyle Boatright" > wrote in
...
>
> "JP" > wrote in message
> ...

<snip>

>> Many prewar (WWII) fighters used wooden propellers. During the war the
>> British fighters like Spitfires and Hurricanes as well as German Me-109's
>> and FW-190's were equipped with metal blade propellers. This can be seen
>> in e.g. photographs presenting downed planes. The bent blades are often
>> clearly visible.
>>
>> JP
>
> At one time or another, all of those aircraft flew behind wooden props.
> Do a google search for "Wood Rotol propeller spitfire", for example.
>
> KB

You're right. Rotol did manufacture wooden blade constant speed propellers
at least three and four-blade models.

JP

cavelamb himself
April 5th 07, 05:19 PM
Kyle Boatright wrote:

> Those of us who fly behind (or in front of) wooden props usually reduce RPM
> significantly when entering rain. I reduce RPM to <1900 in rain, or I see
> minor damage, despite the urethane leading edges. For me, 1900 rpm results
> in a rotational tip speed of about 400 mph. This doesn't consider the
> forward motion of the aircraft.
>
> In WWII, more than a few combat aircraft used wooden propellers - Spitfires,
> Hurricanes, and Me-109's being high profile examples. However, I have never
> heard of any rain/prop issues with those aircraft. And I'm sure there were
> plenty of occasions where those aircraft were flown full-out in rain. FYI,
> with the Spit/merlin combination, the prop is geared to roughly half the
> engine speed of 3,000 RPM. At 1500 prop rpm, a 10.75' diameter prop has a
> tip speed of roughly 575 mph.
>
> That's the kind of tip speed that will supposedly wreck a wooden prop in the
> rain. So, what was different about those props? Were the blades
> essentially disposable and nobody gave a second thought to trashing a set?
> Did the blades incorporate some sort of technology that I've missed? (Brass
> leading edges don't count - to the best of my knowledge, Spits didn't have
> 'em.)
>
> Thoughts?
>
> KB
>
>
>
>
>

I believe most of those old wood props had a brass leading edge cover.
That ought to protect the wood from rain erosion.

OTOH, the (metal) tail rotor on the Hughes OH6A woudld last about 5
minutes in rain.


Richard

Kyle Boatright
April 6th 07, 02:01 AM
"cavelamb himself" > wrote in message
link.net...
> Kyle Boatright wrote:
>
>> Those of us who fly behind (or in front of) wooden props usually reduce
>> RPM significantly when entering rain. I reduce RPM to <1900 in rain, or
>> I see minor damage, despite the urethane leading edges. For me, 1900 rpm
>> results in a rotational tip speed of about 400 mph. This doesn't consider
>> the forward motion of the aircraft.
>>
>> In WWII, more than a few combat aircraft used wooden propellers -
>> Spitfires, Hurricanes, and Me-109's being high profile examples.
>> However, I have never heard of any rain/prop issues with those aircraft.
>> And I'm sure there were plenty of occasions where those aircraft were
>> flown full-out in rain. FYI, with the Spit/merlin combination, the prop
>> is geared to roughly half the engine speed of 3,000 RPM. At 1500 prop
>> rpm, a 10.75' diameter prop has a tip speed of roughly 575 mph.
>>
>> That's the kind of tip speed that will supposedly wreck a wooden prop in
>> the rain. So, what was different about those props? Were the blades
>> essentially disposable and nobody gave a second thought to trashing a
>> set? Did the blades incorporate some sort of technology that I've missed?
>> (Brass leading edges don't count - to the best of my knowledge, Spits
>> didn't have 'em.)
>>
>> Thoughts?
>>
>> KB
>>
>>
>>
>>
>>
>
> I believe most of those old wood props had a brass leading edge cover.
> That ought to protect the wood from rain erosion.

I'm 99% sure that the props I'm talking about didn't have brass leading
edges. The next time you're at an airshow where a Spitfire is on display,
take a close look at the prop. On many (most?, all?) the prop is wood, and
you can't see a transition between a brass leading edge and the wood blade.
I've done this inspection several times at Osh and SnF...

KB

>
> OTOH, the (metal) tail rotor on the Hughes OH6A woudld last about 5
> minutes in rain.
>
>
> Richard

cavelamb himself
April 6th 07, 03:41 AM
Kyle Boatright wrote:
> "cavelamb himself" > wrote in message
> link.net...
>
>>Kyle Boatright wrote:
>>
>>
>>>Those of us who fly behind (or in front of) wooden props usually reduce
>>>RPM significantly when entering rain. I reduce RPM to <1900 in rain, or
>>>I see minor damage, despite the urethane leading edges. For me, 1900 rpm
>>>results in a rotational tip speed of about 400 mph. This doesn't consider
>>>the forward motion of the aircraft.
>>>
>>>In WWII, more than a few combat aircraft used wooden propellers -
>>>Spitfires, Hurricanes, and Me-109's being high profile examples.
>>>However, I have never heard of any rain/prop issues with those aircraft.
>>>And I'm sure there were plenty of occasions where those aircraft were
>>>flown full-out in rain. FYI, with the Spit/merlin combination, the prop
>>>is geared to roughly half the engine speed of 3,000 RPM. At 1500 prop
>>>rpm, a 10.75' diameter prop has a tip speed of roughly 575 mph.
>>>
>>>That's the kind of tip speed that will supposedly wreck a wooden prop in
>>>the rain. So, what was different about those props? Were the blades
>>>essentially disposable and nobody gave a second thought to trashing a
>>>set? Did the blades incorporate some sort of technology that I've missed?
>>>(Brass leading edges don't count - to the best of my knowledge, Spits
>>>didn't have 'em.)
>>>
>>>Thoughts?
>>>
>>>KB
>>>
>>>
>>>
>>>
>>>
>>
>>I believe most of those old wood props had a brass leading edge cover.
>>That ought to protect the wood from rain erosion.
>
>
> I'm 99% sure that the props I'm talking about didn't have brass leading
> edges. The next time you're at an airshow where a Spitfire is on display,
> take a close look at the prop. On many (most?, all?) the prop is wood, and
> you can't see a transition between a brass leading edge and the wood blade.
> I've done this inspection several times at Osh and SnF...
>
> KB
>

Sorry 'bout that, Kyle.

I was thinking Spads and Sopwiths...

Richard

SkyDaddy
April 10th 07, 08:25 PM
On Apr 5, 9:01 pm, "Kyle Boatright" > wrote:
> "cavelamb himself" > wrote in message
>
> link.net...
>
>
>
>
>
> > Kyle Boatright wrote:
>
> >> Those of us who fly behind (or in front of) wooden props usually reduce
> >> RPM significantly when entering rain. I reduce RPM to <1900 in rain, or
> >> I see minor damage, despite the urethane leading edges. For me, 1900 rpm
> >> results in a rotational tip speed of about 400 mph. This doesn't consider
> >> the forward motion of the aircraft.
>
> >> In WWII, more than a few combat aircraft used wooden propellers -
> >> Spitfires, Hurricanes, and Me-109's being high profile examples.
> >> However, I have never heard of any rain/prop issues with those aircraft.
> >> And I'm sure there were plenty of occasions where those aircraft were
> >> flown full-out in rain. FYI, with the Spit/merlin combination, the prop
> >> is geared to roughly half the engine speed of 3,000 RPM. At 1500 prop
> >> rpm, a 10.75' diameter prop has a tip speed of roughly 575 mph.
>
> >> That's the kind of tip speed that will supposedly wreck a wooden prop in
> >> the rain. So, what was different about those props? Were the blades
> >> essentially disposable and nobody gave a second thought to trashing a
> >> set? Did the blades incorporate some sort of technology that I've missed?
> >> (Brass leading edges don't count - to the best of my knowledge, Spits
> >> didn't have 'em.)
>
> >> Thoughts?
>
> >> KB
>
> > I believe most of those old wood props had a brass leading edge cover.
> > That ought to protect the wood from rain erosion.
>
> I'm 99% sure that the props I'm talking about didn't have brass leading
> edges. The next time you're at an airshow where a Spitfire is on display,
> take a close look at the prop. On many (most?, all?) the prop is wood, and
> you can't see a transition between a brass leading edge and the wood blade.
> I've done this inspection several times at Osh and SnF...
>
> KB
>
>
>
>
>
> > OTOH, the (metal) tail rotor on the Hughes OH6A woudld last about 5
> > minutes in rain.
>
> > Richard- Hide quoted text -
>
> - Show quoted text -- Hide quoted text -
>
> - Show quoted text -

The MK XIV Spit had a five-bladed wooden prop. Ironically, the
manufacturer is now owned by a German conglomerate.

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