What Are These things?

[LostElement]

I noticed it on planes, and my friend told me these things were important, but he couldn't remember what these were called and what their function was.

Can someone tell me what these are, and what they do?

 

[Capt. Vick]

Short answer: That is a pitot tube and is essential for the proper function of various instruments in the cockpit.

 

[Crimea_River]

It's for measuring air speed. The tip needs to be located in undisturbed air.

 

[GregP]

The pitot tube gives you ram air pressure and is a right angles to the incoming air. The static port is 90° to the air rushing by and gives static pressure. The difference gives airspeed, rate of climb, and is also used for altitude.

The system is called the Pitot-Static system. If you google it there are some great explanations out there.

 

[GrauGeist]

Also used on modern aircraft for flight system computer telemetry input (input as mentioned in previous posts)

It was also iced-over pitot tubes that contributed to a system failure aboard the Air France Airbus that crashed a few years back.

 

[Wurger]

Pitot-static system - Wikipedia, the free encyclopedia

 

[DerAdlerIstGelandet]

Always check them for ice and anything else that could be blocking them before takeoff. Bad stuff can happen...

 

[bobbysocks]

Also used on modern aircraft for flight system computer telemetry input (input as mentioned in previous posts)

It was also iced-over pitot tubes that contributed to a system failure aboard the Air France Airbus that crashed a few years back.

which puzzles me because most if not all commercial ac have a heating element to keep that from happening....unless the heater wasnt working unbeknownst to the pilots

 

[Airframes]

Even with heating, it can freeze. In Europe in particular, there is a condition known as 'Damp Cold', which is a nasty form of icing which remains between moisture and 'full' ice, which can cause all sorts of problems. One particular Cessna 182 I was waiting to jump from on a cold, damp January day, crashed on approach, a few yards short of the runway threshold, due to 'Damp Cold' freezing in the carb, even though carb heat was on. Fortunately, the pilot and Jumpmaster were OK.

 

[GrauGeist]

The storm system Air France was passing through was extremely unsettled which would have warm and cold moisture even at those altitudes. All it would take, is a blast of warm, moist vapor in the updraft hitting the pitot, followed by sudden sub-zero temps and you have a plug.

 

[Capt. Vick]

Always check them for ice and anything else that could be blocking them before takeoff. Bad stuff can happen...

Watched an Air Disasters episode once and there was a Turkish airliner that was not properly "buttoned up" during something like a month on the ground. It was lost over the south Atlantic (I believe) and they theorized that insects had made homes in the pitot tube sending conflicting information to the flight crew which they just couldn't sort out.

Also read an account of a B-58 Hustler pilot, who during a preflight before a record attempt flight found a cigarette butt stuffed up the pitot tube.

 

[bobbysocks]

i can see a carb icing up even with the carb heat on....you are basically getting warmed air from over the exhaust manifold directed into the carb....and though warmed to the point where you lose ~100 rpm that air isnt that hot. the pitot tubes on the small turbo props i used to work with would get hot enough to burn you if you put your hand on it. evidently it can happen because it did...i just have a hard time wrapping my head around it.

 

[ProudKerman]

Is it just me or does it seem very long,its definitely pitot but dayum its long compared to most others Ive seen

 

[bobbysocks]

the fw 190 had a long one as well...

 

[gumbyk]

Watched an Air Disasters episode once and there was a Turkish airliner that was not properly "buttoned up" during something like a month on the ground. It was lost over the south Atlantic (I believe) and they theorized that insects had made homes in the pitot tube sending conflicting information to the flight crew which they just couldn't sort out.

It's not that hard to sort out, I've had it happen.
Took a Cherokee flying with a customer who was looking to purchase it, and made the mistake of asking him to preflight. The aircraft had just been washed, and someone had put masking tape over the pitot to stop water getting in. We made it back O.K. but it took lots of concentration. That was when I realised why my instructor used to cover all the instruments occasionally!

 

[GrauGeist]

..the pitot tubes on the small turbo props i used to work with would get hot enough to burn you if you put your hand on it. evidently it can happen because it did...i just have a hard time wrapping my head around it.

Sure, it was sitting on the ground at surface temps when it was hot to the touch...but you get up to 30,000 feet or so, and you're dealing with serious sub-zero temps that can flash-freeze moisture in seconds. Add to the already cold temperature, the wind-chill factor that high speed travel can create, too.

You can also encounter these cold temps at lower altitudes if you pass through a cumulus structure that's drawing those sub-zero temps into a down-draft.

 

[nuuumannn]

which puzzles me because most if not all commercial ac have a heating element to keep that from happening....unless the heater wasnt working unbeknownst to the pilots

As part of A-Check inspections we do testing of the pitot static heat elements. A-Checks are carried out every 500 hours.

Here's evidence of pitot static system failures due to ice, AF447, probably the most high profile incident of recent years and Air New Zealand A320 on loan to XL in Europe;

https://en.wikipedia.org/wiki/Air_France_Flight_447

Pilot error, frozen sensors behind Air NZ A320 crash | Australian Aviation

 

[DerAdlerIstGelandet]

Always check them for ice and anything else that could be blocking them before takeoff. Bad stuff can happen...

Watched an Air Disasters episode once and there was a Turkish airliner that was not properly "buttoned up" during something like a month on the ground. It was lost over the south Atlantic (I believe) and they theorized that insects had made homes in the pitot tube sending conflicting information to the flight crew which they just couldn't sort out.

Also read an account of a B-58 Hustler pilot, who during a preflight before a record attempt flight found a cigarette butt stuffed up the pitot tube.

Yeap, everytime I preflight I look into the pitot tubes.

In the hangar we put little foam balls with streamers on them, so people don't walk into them and injure themselves. Anyhow, we where checking the pitot heat and someone forgot to pull them off. Wonderful burning smell as the balls began to melt.

 

[DerAdlerIstGelandet]

i can see a carb icing up even with the carb heat on....you are basically getting warmed air from over the exhaust manifold directed into the carb....and though warmed to the point where you lose ~100 rpm that air isnt that hot. the pitot tubes on the small turbo props i used to work with would get hot enough to burn you if you put your hand on it. evidently it can happen because it did...i just have a hard time wrapping my head around it.

In a thunderstorm with super freezing temps that ice can build up and crust around it at. Continue to build to the point it never unfreezes.

 

[DerAdlerIstGelandet]

It's not that hard to sort out, I've had it happen.
Took a Cherokee flying with a customer who was looking to purchase it, and made the mistake of asking him to preflight. The aircraft had just been washed, and someone had put masking tape over the pitot to stop water getting in. We made it back O.K. but it took lots of concentration. That was when I realised why my instructor used to cover all the instruments occasionally!

Yeap!

Cherokee, thats what I am currently flying. For instruments I will be movibg over to an Archer.