Hi,I live in a very hot humid place and this heat and humidity got me thinking, how hot do airports get during the summer? Like in a very hot humid place how hot does it get. And does it effect the aircraft. Like the density of the air and how much it effects the lift when taking off and landing. Also the engines, when temperatures are higher they have to use less thrust cause it can get really hot right? How does it compare to the winter time?

Here in Australia you get hot temps but airfield elevation in not overly high for example on the coast at sealevel its not unusual to see 42+deg c temps in summer. so quick maths tell you that your up at least 3000' Plus Density Alt (DA) On the runway.however the highest airport i the world now which is Bangda in eastern Tibet is 15,548' on the ground. and temps in summer are only around 15Deg C.It does also have the worlds longest runway as a result of near 18,500' or 5,500Metres.

Here in Honolulu it can get to just above 32C sometimes. This does lead to longer takeoff runs and slightly slower cruising speeds. Regarding thrust, it's not that we need to use less. We actually need to use more to get the same performance but the engine is incapable of producing that much power. The problem (turbine or piston) is that with hotter and even humid conditions, the air density is less. This means that it has less air compared to denser air conditions to work with.We call this density altitude, which really actually takes more temperature and air pressure into account. Humidity does have an effect but it's small enough where its not too much of a concern. Basically, density altitude is the altitude the aircraft 'thinks' it's at. For example, say it's standard pressure (29.92in or 1013mb) but it's 32C degrees out and your at HNL (13ft elevation but we'll keep it simple and use 0ft). Your altimeter will read 0 but your aircraft will perform as if it were at about 1900 ft. Thus although your true altitude is 0, your density altitude is 1900ft. As I'm typing this, the conditions at HNL are 29 degrees and A3001. Given that, the aircraft will behave as if it were at 1500ft while it is on the ground.Conversely in the winter here, the temperature sometimes gets to a down right icy 18 degrees centigrade (sorry, couldn't help it). Assuming that temperature but still A3001, the aircraft will perform as if it were at just 200ft. The colder it gets or the higher the altimeter setting, the better the performance is. The reason once again is how much air particles are in a given volume of air. It's almost like breathing, the less air there is, the worse your perform.

Is 32 degrees the runway temperature or the temperature of Honolulu? So during the winter the air is more dense and during the summer its less dense. This does have effect on lift such as when approaching in the winter you need less speed than approaching in the summer, right?

Is 32 degrees the runway temperature or the temperature of Honolulu? So during the winter the air is more dense and during the summer its less dense. This does have effect on lift such as when approaching in the winter you need less speed than approaching in the summer, right?

It's the temperature at the airport. I will be honest though, I don't know where on the airfield the wx instruments are located. And as far as air density, generally yes, in the winter it's denser and during the summer it's less. But keep in mind that pressure and temperature is what determines density. If it's an abnormally hot winter day with say A29.67, your are going to have air that is less dense. Opposite if it's a cold summer day with a high altimeter setting.And yes, lift is also one of the additional factors that is affected by density altitude. But your speed indicated on your instruments during approach will remain the same for the most part. The determining factor there is weight, not so much density altitude. The reason is that if the density altitude is higher (this means higher altitude, not higher density), there is less air to ram into the pitot system. Less air means a smaller indication. To adjust, you fly faster so you indicate say a normal approach speed of 70KIAS and so now your wings still have 70kts worth of airspeed flowing over it. This is also done automatically since usually the only speed indication used during approach is your ASI. Looking at that your won't notice if you're flying faster or slower than normal. So 70KIAS at high density altitude is still the same as 70KIAS at low density altitude. It's your ground speed that will be different.

I have a story about hot airfields (I can hear everyone now; "Great, here he goes again!")...I trained to fly initially on a Mooney Cadet (M210). My second solo cross country was a flight from Brown Field in San Diego county, Calif. to Palm Springs. Palm Springs is located almost in the desert. The only worse place to fly into in that area is Bythe. The route for the flight was due east from Brown field, and once over the mountains, turn north to Palm Springs. Oh, did I mention this was in July? The importance of that fact did not strike home until entering final at Palm Springs. Normally the M210 glides like a rock. Not over the end of an asphalt runway in the heat of July in Palm Springs. The thermal rising off the end of the runway was so great that I had to do a slip to get the 210 on the ground. I was very happy to have packed a change of underwear. Where was my first solo to? Blythe of course. Brown via Julian VOR to Blythe, refuel, and then down the Colorado river turning due west horizontal to Yuma. Stop at Imperial and then over the mountains back into Brown.

It's the temperature at the airport. I will be honest though, I don't know where on the airfield the wx instruments are located. And as far as air density, generally yes, in the winter it's denser and during the summer it's less. But keep in mind that pressure and temperature is what determines density. If it's an abnormally hot winter day with say A29.67, your are going to have air that is less dense. Opposite if it's a cold summer day with a high altimeter setting.And yes, lift is also one of the additional factors that is affected by density altitude. But your speed indicated on your instruments during approach will remain the same for the most part. The determining factor there is weight, not so much density altitude. The reason is that if the density altitude is higher (this means higher altitude, not higher density), there is less air to ram into the pitot system. Less air means a smaller indication. To adjust, you fly faster so you indicate say a normal approach speed of 70KIAS and so now your wings still have 70kts worth of airspeed flowing over it. This is also done automatically since usually the only speed indication used during approach is your ASI. Looking at that your won't notice if you're flying faster or slower than normal. So 70KIAS at high density altitude is still the same as 70KIAS at low density altitude. It's your ground speed that will be different.

so air density effects pitot tubes? So if the approach speed in winter was 140 knots it would be indicated the same in summer?To be honest I thought it would effect them much more, any other instruments effected by this? Meteorology is hard to understand

so air density effects pitot tubes? So if the approach speed in winter was 140 knots it would be indicated the same in summer?To be honest I thought it would effect them much more, any other instruments effected by this? Meteorology is hard to understand

The best way to see the effects is when you're climbing. Look at the MD11 for example. Your TAS (the speed the aircraft is moving through the air) is something like 490kts. But you'll notice that your ASI only indicates less than 300kts above FL350. This is because the air pressure (and density) is much lower than at sea level. The pitot tube measures airspeed by comparing the static pressure to the pressure generated by air being forced into the pitot system. With less pressure (and density), there is less stuff to build up pressure in the tube itself.

The best way to see the effects is when you're climbing. Look at the MD11 for example. Your TAS (the speed the aircraft is moving through the air) is something like 490kts. But you'll notice that your ASI only indicates less than 300kts above FL350. This is because the air pressure (and density) is much lower than at sea level. The pitot tube measures airspeed by comparing the static pressure to the pressure generated by air being forced into the pitot system. With less pressure (and density), there is less stuff to build up pressure in the tube itself.

so is that why the computer needs to know the air pressure and temperature outside to calculate the actual airspeed? I notice the same thing on the 747 as well.

so is that why the computer needs to know the air pressure and temperature outside to calculate the actual airspeed? I notice the same thing on the 747 as well.

Sort of. The computer needs to know the pressure altitude which when your altimeter is set to standard, is what is indicated. If it's set to local altimeter, the computer can automatically figure out what the pressure altitude is anyway. If you have both the pressure altitude and temperature and know the formula or have a calculator, you can compute it yourself too. You may notice the movable card on the ASI of small GA aircraft like C172s. You use the small window at the top to line up your pressure altitude against the current OAT on the temperature card. The movable airspeed card will then show your TAS while the stationary section of the instrument always shows IAS.

KPHX was nearly shut down yesterday here - we got to 118, they'll shut it down at 120.

KPHX was nearly shut down yesterday here - we got to 118, they'll shut it down at 120.

It was 110 in Vegas yesterday..... I am from the southeast were it is humid and 85 but 110 and dry makes you want to die it's so hot. Though, the Mandalay Bay has an awesome "waterpark"--The water is "refrigerated" to about 85-90.--It feels awesome!I am leaving for ATL tomorrow afternoon; thankfully the high temp is only 100 not 120. lol

KPHX was nearly shut down yesterday here - we got to 118, they'll shut it down at 120.

I thought airports can stand up to about 140, thats nearly how hot it got at haneda last year

At prince sultan ab. in saudi we saw surface temps on the tarmac of 140 f. nasty stuff. the patrols were still flying though.

I didn't know there was a maximum temperature before airports are closed. I'm guessing it has to do with aircraft performance?Interestingly I read an article where airports are forced to close when the temperature drops below a certain level. I tried to find it but I don't have a clue which issue it was in. (It was a printed magazine) It isn't because if fuel freezing or anything like that. It's because the air is so cold and dense the altimeters wouldn't indicate correctly if you set the current altimeter setting in the window.