Tire inflation pressure

45 lbs??? 55 lbs for the nose gear??? That seems awfully high. Those tires
will be hard as a rock. I guess I'd prefer a little softer tire to land on. I
rarely put in more than about 15 to 20 lbs. 5 lbs will "get the sidewall off
the ground."

(VideoFlyer) wrote:

45 lbs??? 55 lbs for the nose gear??? That seems awfully high. Those tires
will be hard as a rock. I guess I'd prefer a little softer tire to land on. I
rarely put in more than about 15 to 20 lbs. 5 lbs will "get the sidewall off
the ground."

You obviously don't have experience with 5.00-5 tires on a 2,250 lb
gross weight canard aircraft or you wouldn't be spewing such
ignorance. The pressures I gave are correct for the tires, weight,
and configuration. 15 to 20 psi 5.00-5 tires would be grossly under
inflated on that airplane. The nose tire inflation of 55 psi is also
correct. Think before you post, people.

- anon

anon wrote:

(VideoFlyer) wrote:

45 lbs??? 55 lbs for the nose gear??? That seems awfully high. Those tires
will be hard as a rock. I guess I'd prefer a little softer tire to land on. I
rarely put in more than about 15 to 20 lbs. 5 lbs will "get the sidewall off
the ground."

You obviously don't have experience with 5.00-5 tires on a 2,250 lb
gross weight canard aircraft or you wouldn't be spewing such
ignorance. The pressures I gave are correct for the tires, weight,
and configuration. 15 to 20 psi 5.00-5 tires would be grossly under
inflated on that airplane. The nose tire inflation of 55 psi is also
correct. Think before you post, people.

Consider that a pneumatic tire supports the weight by the air pressure
that's in it - and that the contact patch of the tire is approximately
the weight on the tire in pounds divided by the pressure in psi. That
means on the hypothetical plane above (2,250 pounds, 15psi), the
contact patch (total) for the three tires would be around 150 square
inches. That's 50 square inches per tire, which on a 5.00 tire is
otherwise known as "a flat".

Mark Hickey

Mark Hickey wrote:


Consider that a pneumatic tire supports the weight by the air pressure
that's in it - and that the contact patch of the tire is approximately
the weight on the tire in pounds divided by the pressure in psi. That
means on the hypothetical plane above (2,250 pounds, 15psi), the
contact patch (total) for the three tires would be around 150 square
inches. That's 50 square inches per tire, which on a 5.00 tire is
otherwise known as "a flat".

Mark Hickey

Agreed. More accurately, however, for this airplane there would be
about 1000 lb on each main at gross weight which, as you note, would
result in very flat 5.00-5 tires at 15 psi. The 45 psi recommendation
is correct.

- anon

Well....you're right, -anon. I obviously have no experience with 5:00-5 tires
on a 2250 lb gross weight canard aircraft or I wouldn't be "spewing" such
ignorance. But you might notice that I didn't say in my post that 15-20 lbs was
the correct, or even recommended, pressure. I am sorry to have contaminated
this group with an opinion, an observation and personal experience. Mea culpa,
mea culpa.

My experience with 5:00-5 tires is on much lighter aircraft. And while I
didn't mean to be "spewing ignorance" my experience nonetheless is that
pressures of 45-55 lbs makes the tires on my Rans pretty hard. If you would
like to tell me that my experience is not valid somehow, feel free.

To the original poster...if you want truly accurate information on this
newsgroup, "anon" is the person you want to consult. If you're looking for
feedback from other people interested in this hobby, better check with "-anon"
as well...just so you don't get splattered with more "spewed ignorance."

Flyer (foot firmly implanted in mouth)

(VideoFlyer) wrote:

Well....you're right, -anon. I obviously have no experience with 5:00-5 tires
on a 2250 lb gross weight canard aircraft or I wouldn't be "spewing" such
ignorance. But you might notice that I didn't say in my post that 15-20 lbs was
the correct, or even recommended, pressure. I am sorry to have contaminated
this group with an opinion, an observation and personal experience. Mea culpa,
mea culpa.

My experience with 5:00-5 tires is on much lighter aircraft. And while I
didn't mean to be "spewing ignorance" my experience nonetheless is that
pressures of 45-55 lbs makes the tires on my Rans pretty hard. If you would
like to tell me that my experience is not valid somehow, feel free.

While your experience is of course valid, in this case it wasn't
relevant to the poster's question. The poster's 5.00-5 tires must
support about 1000 # each at gross weight. That fact dictates the
minimum tire pressures. And let's not pretend to be the wounded
innocent. Your post was written in direct rebuttal to my post and
called my pressure recommendations into question. Yours wasn't the
innocent ancillary informational post that you now pretend. In
retrospect, however, I should have used more tact. For the record,
here is your post:

45 lbs??? 55 lbs for the nose gear??? That seems awfully high. Those tires
will be hard as a rock. I guess I'd prefer a little softer tire to land on. I
rarely put in more than about 15 to 20 lbs. 5 lbs will "get the sidewall off
the ground."

- anon

anon wrote:
(VideoFlyer) wrote:


Well....you're right, -anon. I obviously have no experience with 5:00-5 tires
on a 2250 lb gross weight canard aircraft or I wouldn't be "spewing" such
ignorance. But you might notice that I didn't say in my post that 15-20 lbs was
the correct, or even recommended, pressure. I am sorry to have contaminated
this group with an opinion, an observation and personal experience. Mea culpa,
mea culpa.

My experience with 5:00-5 tires is on much lighter aircraft. And while I
didn't mean to be "spewing ignorance" my experience nonetheless is that
pressures of 45-55 lbs makes the tires on my Rans pretty hard. If you would
like to tell me that my experience is not valid somehow, feel free.


While your experience is of course valid, in this case it wasn't
relevant to the poster's question. The poster's 5.00-5 tires must
support about 1000 # each at gross weight. That fact dictates the
minimum tire pressures. And let's not pretend to be the wounded
innocent. Your post was written in direct rebuttal to my post and
called my pressure recommendations into question. Yours wasn't the
innocent ancillary informational post that you now pretend. In
retrospect, however, I should have used more tact. For the record,
here is your post:


45 lbs??? 55 lbs for the nose gear??? That seems awfully high. Those tires
will be hard as a rock. I guess I'd prefer a little softer tire to land on. I
rarely put in more than about 15 to 20 lbs. 5 lbs will "get the sidewall off
the ground."


- anon


How about this that I learned from the Dodge Dakota newsgroup a while
back? Forget about tire pressure for now. Load up the plane to what
you expect to be the normal operating weight. Pump up the tire untill
you get full tread and no sidewall contact. Take the tire pressure and
use that from then on.

How do you know when you've got full tread contact? Pour some water
just in front of the tire and pull the plane through it, letting the
wheel turn completely over a couple of times. It'll leave an 'imprint'
on the second time around that will be a mirror image of the tread
pattern. If you can read sidewall numbers, you need more air. If it is
just a thin strip, you need to remove some.

--
http://www.ernest.isa-geek.org/
"Ignorance is mankinds normal state,
alleviated by information and experience."
Veeduber

How about this that I learned from the Dodge Dakota newsgroup a while
back? Forget about tire pressure for now. Load up the plane to what
you expect to be the normal operating weight. Pump up the tire untill
you get full tread and no sidewall contact. Take the tire pressure and
use that from then on.

How do you know when you've got full tread contact? Pour some water
just in front of the tire and pull the plane through it, letting the
wheel turn completely over a couple of times. It'll leave an 'imprint'
on the second time around that will be a mirror image of the tread
pattern. If you can read sidewall numbers, you need more air. If it is
just a thin strip, you need to remove some.

--
http://www.ernest.isa-geek.org/
"Ignorance is mankinds normal state,
alleviated by information and experience."
Veeduber



Excellent!!
Been doing it for years. Dont even need the water now.

Warren

"VideoFlyer" wrote in message
...
45 lbs??? 55 lbs for the nose gear??? That seems awfully high.
Those tires
will be hard as a rock. I guess I'd prefer a little softer tire to
land on. I
rarely put in more than about 15 to 20 lbs. 5 lbs will "get the
sidewall off
the ground."


It would depend on the all up weight of the aircraft, our Rallye 100
weighs in at a gross weight of 1700 lbs and the tire pressures are 21
in the nose wheel and 25 in the mains.
--

..
--
Cheers,
Jonathan Lowe
whatever at antispam dot net
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