It hist 90+ way up here in Pennsylvania. I hear it hit 110 in Arizona and Southern, California today, so you are enjoying a nice cool spell.

Record highs and record high low temperatures. 115. Waiting for the rain. So far mostly lightning and fires.

 

I guess you could argue that brakes are a part of the landing gear.. There is probably a max tire/wheel speed too but doubtful that it would be limiting factor in normal use. Big jets have a max landing weight, though. It can be determined by structural as well as other factors and is why they dump fuel in an emergency return.

I was speaking about extreme conditions. Something #12 keeps leaving out. High altitude airport, overloaded aircraft etc.

Now it might be that even on an infinitely long runway, an aircraft can never exceed a speed on the ground to where it can damage the tires. But there still has to be a rated speed on the tires, after that damage will occur. Again it might not even be possible for the fastest jets to get to that point on the ground.

 

I was speaking about extreme conditions. Something #12 keeps leaving out. High altitude airport, overloaded aircraft etc.

Now it might be that even on an infinitely long runway, an aircraft can never exceed a speed on the ground to where it can damage the tires. But there still has to be a rated speed on the tires, after that damage will occur. Again it might not even be possible for the fastest jets to get to that point on the ground.

Yes, I'm sure there's an rpm limit on the tires. Though I don't know what that would be for commercial aircraft.

 

I was speaking about extreme conditions. Something #12 keeps leaving out. High altitude airport, overloaded aircraft etc.
Now it might be that even on an infinitely long runway, an aircraft can never exceed a speed on the ground to where it can damage the tires. But there still has to be a rated speed on the tires, after that damage will occur. Again it might not even be possible for the fastest jets to get to that point on the ground.

I hate not knowing these things so.. attached is an application chart for GoodYear aircraft tires. The ones for the CRJ are rated at 225mph (pp4). That is faster than takeoff speed in most conditions.

I know what you are going to say - how fast for takeoff - so also attached is a list of typical speeds. V2 is the minimum lift off speed. MPH = KNOTS*1.15 so at 50,000lbs, standard temp at sea level it can lift off at 177 MPH. In hot/high conditions, the actual groundspeed would be greater. Poking in a DA of 5000' (1135 elevation of PNX at 118 degF) you get a speed over the ground of about 195 MPH, below the 225mph tire limit but not by much. That is the minimum liftoff speed at gross weight. According to the chart, you could use more flaps and reduce the liftoff speed a bit.

I think what we're seeing is a lot of limitation graphs coming together as the DA gets higher. Gotta draw the line somewhere so someone said 118F.

@WBahn might want to check my math..

 

I hate not knowing these things so.. attached is an application chart for GoodYear aircraft tires. The ones for the CRJ are rated at 225mph (pp4). That is faster than takeoff speed in most conditions.

I know what you are going to say - how fast for takeoff - so also attached is a list of typical speeds. V2 is the minimum lift off speed. MPH = KNOTS*1.15 so at 50,000lbs, standard temp at sea level it can lift off at 177 MPH. In hot/high conditions, the actual groundspeed would be greater. Poking in a DA of 5000' (1135 elevation of PNX at 118 degF) you get a speed over the ground of about 195 MPH, below the 225mph tire limit but not by much. That is the minimum liftoff speed at gross weight. According to the chart, you could use more flaps and reduce the liftoff speed a bit.

I think what we're seeing is a lot of limitation graphs coming together as the DA gets higher. Gotta draw the line somewhere so someone said 118F.

@WBahn might want to check my math..

I do realize that aircraft might be grounded due to safety reasons, weather conditions, weight of aircraft etc. etc.

Again I was speaking in the extreme, or more the absurd. OK you are in Denver, it is 120 F, there is a low pressure system sitting over the airport, the plane is crammed full of people and supplies. It is a matter of life and death that you take off. You are on an extra long runway where you can get to a speed fro those extreme conditions. Do you or do you not risk spinning the tires off of the plane as you approach the end of the runway?

 

I do realize that aircraft might be grounded due to safety reasons, weather conditions, weight of aircraft etc. etc.

Again I was speaking in the extreme, or more the absurd. OK you are in Denver, it is 120 F, there is a low pressure system sitting over the airport, the plane is crammed full of people and supplies. It is a matter of life and death that you take off. You are on an extra long runway where you can get to a speed fro those extreme conditions. Do you or do you not risk spinning the tires off of the plane as you approach the end of the runway?

I'm not much of a plane connoisseur... but I'd expect that the speed needed for the tires to be affected would be much higher than the speed at which the plane would take off by itself, or at which the aerodynamic forces on the ground become dangerous.

 

I hate not knowing these things so..

me too... and just love the way you stated it...

 

I do realize that aircraft might be grounded due to safety reasons, weather conditions, weight of aircraft etc. etc.

Again I was speaking in the extreme, or more the absurd. OK you are in Denver, it is 120 F, there is a low pressure system sitting over the airport, the plane is crammed full of people and supplies. It is a matter of life and death that you take off. You are on an extra long runway where you can get to a speed fro those extreme conditions. Do you or do you not risk spinning the tires off of the plane as you approach the end of the runway?

If it is a matter of life and death that you take off, why does it matter whether you think the tires might spin off? If you don't take off, it is death -- so what do you have to lose by attempting to take off?

 

If it is a matter of life and death that you take off, why does it matter whether you think the tires might spin off? If you don't take off, it is death -- so what do you have to lose by attempting to take off?

It's always nice to know how you're going to go. I'd rather have my cause of death be listed as "catastrophic tire failure" than "lack of lift caused by high temperatures and low atmospheric pressure". Maybe @spinnaker feels the opposite.

 

A picture says a thousand words:

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A picture says a thousand words:

View attachment 129577​

Holy crap. Is that a shot an outside door from the inside? Or an outside door from the outside?

 

It's always nice to know how you're going to go. I'd rather have my cause of death be listed as "catastrophic tire failure" than "lack of lift caused by high temperatures and low atmospheric pressure". Maybe @spinnaker feels the opposite.

Arguably the cause of death is the latter in either case -- or in neither case. This would be the instigating factor in both cases while the direct cause would be something more like blunt force trauma or blast injury.

 

Holy crap. Is that a shot an outside door from the inside? Or an outside door from the outside?

Outside door from the outside. The sun was shining directly onto the doorknob.

 

Outside door from the outside. The sun was shining directly onto the doorknob.

Get the wife to knit you some door knob cozies

 

out of asbestos

 

Outside door from the outside. The sun was shining directly onto the doorknob.

That's not fair. Sun shining on any surface can result in elevated temperatures. When the sun shines on my outdoor thermometer, the needle goes off scale pass 50°C while the air temperature is below 25°C.

What was the air temperature?

 

What was the air temperature?

It was 43C at the time

 

how come?

Actually other than smog and air quality taxes come to mind. This was the modest 2 bedroom house I grew up in. About 20 miles outside NYC. My parents bought that house new in 1953. The upper was just attic and the dormer came later upstairs. The cost was $12,500 new. The picture is 2000. The old neighborhood has changed. Today the taxes on that house are about $20,000 USD per year. We sold in 1966 for about $20,000 USD. Taxes are OK but one needs to look at what one gets for their taxes.

As many here know I am an avid shooter, I love the shooting sports. Both NY and CA have very restrictive gun control laws. Laws restricting my rights as a US citizen. I have no use for laws which restrict my constitutional rights, especially my rights to protect my home and property. Nope I have no use for NY or CA.

Ron

 

put your hand on an old fashion car handle.......or try to pick up a wrench........you will not care about the air temp.
Only experienced those temps once......and it caused extreme thunderstorms.
does that happen down there.......or you just wait for it to pass.\


edit....what's your humidity? my high temps were wet.....are you dry?

 

put your hand on an old fashion car handle.......or try to pick up a wrench........you will not care about the air temp.
Only experienced those temps once......and it caused extreme thunderstorms.
does that happen down there.......or you just wait for it to pass.

I understand. And I know about the "unfairness" of my pic... but still, you have to admit that it pretty much makes a point, right?