Questions tagged [pitot-static]
A pressure-based system for measuring airspeed and altitude.
86
questions
2
votes
1
answer
117
views
How does this total energy compensation pitot tube work?
This is a pitot tube I saw on a glider:
The far right end plugs into a receiver. The far left end has the RAM port at the tip, the static ports just behind it, drilled in laterally, and a venturi ...
3
votes
0
answers
46
views
Pressure scanner for multi-hole Pitot-static probe going to 100km altitude and M3.5
I am wondering if anyone has experience in looking for multi-channel differential pressure scanners for use with pitot static probes in aerospace? What companies/manufacturers/product familes would ...
0
votes
2
answers
138
views
How would IAS change with altitude for an unpowered parafoil?
Suppose an unpowered parafoil (e.g. a ram air parachute or paraglider) is descending (gliding) in a standard atmosphere. Suppose a pitot tube is positioned to always point into the relative wind (e.g. ...
0
votes
2
answers
151
views
Is there a certain minimum temperature we need to turn on pitot heat on light trainer aircraft (eg DA40NG)?
Is there a certain minimum temperature we need to turn on pitot heat on light trainers (eg DA40NG)?
In the AFM and checklist documents for the DA40NG, information is given that it should only be ...
4
votes
2
answers
206
views
How the placement of the pitot and static ports decided?
Forgive the this topic placement as it might be similar to other older ones (Although I a bit sure that the main contents might be different than other older ones).
In the upcoming days I will have a ...
2
votes
0
answers
125
views
Air density factor when calculating Airspeed
I am making my own attitude indicator / AHRS, like a Garmin G5. I am using two pressure sensors to measure altitude & airspeed via static /pitot lines.
Now I know the formula for calculating ...
5
votes
2
answers
713
views
Why do experimental aircraft have such long tubes on the nose?
Why do experimental aircrafts (like the X-35, the Space Shuttle Enterprise, the H160 or the X-15 in the pictures) have such long Pitot tubes at the nose when compared to the production aircraft? Are ...
0
votes
6
answers
2k
views
Please describe ram pressure in simple terms [duplicate]
Please someone describe the following sentence in simple words:
The Airspeed Indicator is calibrated for 'standard' sea level density, so it will only read TAS if the density of the air through which ...
11
votes
1
answer
886
views
On the A330 why does switching off the ADRs require alternate LG extension and inhibit nose wheel steering?
In the incident examined in this video the pilots experienced an unreliable airspeed indication due to pitot tube blockage in an A330. They followed the abnormal checklist for unreliable airspeed ...
0
votes
1
answer
306
views
Does static pressure(p - p∞) at wing surface change exponentially, with square of the velocity?
Integration of static pressure over wing we get lift.
and
Formula for lift is L= 1/2 x Cl x A x V2 x ro;
that implies that static pressure (p - p∞) change exponentially(as square of velocity), becuase ...
6
votes
3
answers
1k
views
Do pitot tubes account for reduced pressure at altitude?
Do pitot tubes account for reduced pressure at altitude?
Does indicated airspeed reduce with altitude? If so, how much?
Is it different for small planes vs big commercial airliners?
4
votes
1
answer
414
views
Why might flight schools prohibit you from testing pitot heat during pre-flight?
Why might flight schools prohibit you from testing pitot heat during pre-flight? I know of a school in Texas that has this policy but don’t understand why.
Here is a snippet of the C172 AFM which ...
6
votes
1
answer
351
views
How long does a pitot tube last?
Aircraft components need periodic maintenance, this should be the same for the pitot tube that is an essential instrument for pilots. So do you know when should a pitot tube go into maintenance? I can'...
3
votes
1
answer
302
views
How long should a pitot tube extend from the wing?
It seems that most of the pitot tubes are "L" shaped. However, there are some pitot tubes that shapes like a straight pipe. I am wondering that, for a straight pitot tube installed on the ...
-1
votes
1
answer
261
views
Can pitot tube measure boundary layer? Why? [closed]
Can pitot tube measure boundary layer? Why? Why not?
1
vote
0
answers
59
views
Is the use of 1/8 NPT ports on pitot/static instruments derived from an FAA standard?
On almost every pitot-static instrument used in general aviation aircraft, a 1/8 female NPT port is provided to connect the instrument to the pitot-static system. I was told that is is a requirement ...
-3
votes
1
answer
148
views
If the altitude of the aircraft is given by the pitot tube, in icing condition with heat on, how is real altitude /speed interpretation done? [duplicate]
If the altitude of the aircraft is given by the pitot tube, in icing condition with pitot heat on how is real altitude /speed interpretation done? Because the air density and temperature is not ...
1
vote
2
answers
257
views
What are the relations between Angle of attack and Calibrated Airspeed?
I would like to estimate Angle of Attack using trigonometric relations i.e AoA = arctan (w/u) airspeed components (i.e u, v, w). When I am considering body 'x' velocity ('u' component), is it ...
2
votes
0
answers
96
views
Does the airspeed indicator measure speed inaccurately at different angles of attack?
A point of confusion for me has been this: Does the pitot tube measure the airspeed of the plane in the direction of its flight path, or does it measure the speed of the air parallel to the pitot tube ...
4
votes
1
answer
650
views
If an airplane has a Vertical Speed Indicator is there a requirement that it be periodically checked for accuracy?
I believe I understand that there is no specific US FAA requirement for aircraft to carry a Vertical Speed Indicator (VSI). I believe I understand the basic operation of a VSI. It measures the rate ...
3
votes
2
answers
358
views
How can static pressure be obtained over a range of airspeeds? [duplicate]
Multiple instruments rely on static air pressure, i.e. pressure unaffected by airspeed.
To my understanding, no such air should exist around an aircraft. Air in motion exhibits a lower pressure ...
2
votes
1
answer
951
views
Are pitot systems protected from ice?
Aircraft use pitot tubes or pitot-static tubes. Do these have some kind of anti-ice system? If so, how? And if not, why not?
I'll just point out that it doesn't seem trivial to de-ice such a thing. A ...
3
votes
0
answers
90
views
How is airspeed measured on supersonic aircraft? [duplicate]
Behind the shock wave air is subsonic, would that not cause an issue with the pitot tubes or any other sensor?
9
votes
2
answers
3k
views
Why is the pitot tube located near the nose?
The pitot tube located near the nose could be affected by the boundary layer and could increase the error. Then why is the pitot tube located near the nose?
1
vote
4
answers
482
views
What would cause a non-zero indicated airspeed reading on the ground?
What kind of failure would cause an indicated airspeed of say 200 knots on the ground (stationary)?
8
votes
4
answers
2k
views
Why are pitot-static measurements preferred over other velocimetry techniques?
I believe hot wire anemometers (HWA, frequently used in wind tunnels to measure flow velocity) or other sensitive techniques could be used to determine the airspeed. Are there specific reasons for why ...
5
votes
1
answer
366
views
What is the reason for the fence aft of the static ports on some airplanes and helicopters?
Airbus AS350 helicopters and Bell 206 helicopters have a 1/2" long fence behind the static port. CRJ 200/700 have a .060" step on the aft side of the static port. What would be the reason ...
0
votes
1
answer
109
views
How to use a set of Pressure Transducer to mimic pitot static tube for VTOL vertical airspeed indicator?
May i know if i have 3 pressure transducer, 1 facing upwards and the other downwards to measure the vertical velocity of a VTOL (Vertical Takeoff and Landing aircraft) and another 1 on the nose of the ...
5
votes
2
answers
2k
views
Why are some A350s missing SSA probes on their nose?
I recently just noticed that some A350s are missing their iconic set of 3 main SSAs (Side Slip Angle Probes) on their nose. I'm not sure if its an issue of newer variants or varied airline options, ...
0
votes
1
answer
959
views
Why do larger aircraft need two or more static ports?
Some background information:
"Static pressure is the measurement of the ambient barometric pressure at the aircraft’s CURRENT location AND CURRENT Altitude.
The Static Port is located in a position on ...
6
votes
3
answers
627
views
Why does the faster-moving air over the static port not result in a lower static pressure?
I understand the concept that the static port is measuring "static" pressure, meaning the pressure the air is exerting on its surroundings. However, there is also Bernoulli's principle, which, put ...
1
vote
0
answers
133
views
Where is pure outside static air pressure indication on A320?
I'm looking for the indication of the outside static air pressure in the cockpit.
Where is it located? One of the ECAM pages?
Thanks!
4
votes
2
answers
11k
views
Where is the pitot static drain located on a Piper PA-28?
Some PA-28 airplanes have pitot static drain where the pilot pushes 2 buttons to open the system.
But where does the water drip out from the airplane? Is there a hole underneath the airplane? Where? ...
6
votes
1
answer
433
views
Altimeter shows 100 foot drop when power is added. Is this a leak in the static system or broken altimeter and how long will the fix take?
My instructor and I were preparing for my Private Pilot Check ride today when we noticed that the analog altimeter would suddenly lose 100 feet when we added power. The only way I can think to ...
2
votes
5
answers
1k
views
How does static port measures the static pressure?
I have always thought that there is a probe or sensor kind of thing inside the static port so that it "measures" the static pressure and compare to other pressure sources for airspeed, altitude, and ...
1
vote
1
answer
786
views
How does a G1000 equipped with a GDC 74 calculate IAS from dynamic pressure?
How exactly does a G1000 system equipped with a GDC 74 air data computer calculate the indicated airspeed that is displayed on the PFD from difference between the total and static pressure (i.e. ...
2
votes
1
answer
146
views
Pitot tube model
EDIT: Background on my application
I am making a few measurement models for an extended Kalman filter (EKF). The EKF is meshing an INS and a GPS currently, but the GPS update rate does not update ...
0
votes
2
answers
136
views
Pitot tube pressure question
I have this question is the pressure measured in the entry of the pitot tube the same when the plane is flying headwind or turning a 360 degree turn while maintaining the same indicated airspeed?
3
votes
2
answers
271
views
Do any aircraft automatically test that the pitot-static system is functioning properly before liftoff?
Given that a properly-functioning pitot-static system is absolutely essential for flight (a plane cannot be flown without valid airspeed data, or at least not for long), are there aircraft that ...
3
votes
2
answers
469
views
Static port and Bernoulli [duplicate]
Static ports open directly to the outside of fuselage. When aircraft is flying, there will be air flowing outside of static port. How does this not cause a vacuum effect inside the static port. Due to ...
5
votes
5
answers
5k
views
What does the Airspeed indicator show when your pitot tube is blocked?
So the question in the topic.
I want to clarify whether the speed indications is maintained or go to 0.
1
vote
1
answer
421
views
Which company manufactures the air data system on the Boeing 787-9 'Dreamliner'
I'm asking specifically about the manufacturer and model of the Pitot probes/tubes that provide the pilots with current air speed readings.
Pretty sure it's either UTC or Honeywell but can't find ...
15
votes
3
answers
3k
views
Does the pressure at the static ports drop as the aircraft's speed increases?
This answer by Tyler Durden explains what static ports are and how they work:
The "static ports" allow air into the instrument to provide the input for the air pressure on the side of the aircraft. ...
4
votes
2
answers
2k
views
Is it possible to totally override the flight computer on the Airbus A320-family (in simple non-technical terms)?
As I know, in the autopilot oriented airplanes like an A321 the plane doesn't let the pilots pitch down when the plane gets an over-speed warning.
So what if the pitot-static system isn't working ...
2
votes
2
answers
1k
views
Where exactly are the pitot tubes positioned on the A330/340?
While going through a document for analysis I came across a statement saying the positions 1 and 2 of the pitot probes are symmetrical on long-range Airbus aircraft but not on their single-aisle ...
5
votes
1
answer
1k
views
How is the static pressure in the pitot static system reconciled when there are two outside static pressure ports?
On airplanes where there are two static pressure sources (ports) on each side of the fuselage what is the result of the static pressure as compared to aircraft with a single port. (I'm not talking ...
8
votes
1
answer
2k
views
What additional functionality is provided by the F-14 nose pitot, absent in early models?
Early model F-14A had no nose pitot:
... but they seem to have quickly acquired them sometime in the late 1970s. The Iranian F-14s have them, and it's quite hard to find a picture of an F-14 without ...
14
votes
2
answers
13k
views
Why does the Boeing 737 have a pitot tube on the tail?
From this link:
Can anyone explain why the Boeing 737 has a pitot tube for the elevators? Wouldn't the airspeed be measured the same from the front of the airplane and the tail? Is the airspeed ...
0
votes
2
answers
2k
views
What is the meaning of "static pressure"?
I don't really know what static pressure is. Does the ASI (Airspeed Indicator) use cockpit pressure as static pressure, to find the dynamic or differential pressure?
I just found this statement :
...
4
votes
2
answers
619
views
How does the mechanical linkage of the airspeed indicator convert dynamic pressure to KIAS?
I understand the underlying principle of an airspeed indicator, ie. that it uses the Pitot-static system to measure the dynamic pressure as the difference between total pressure and static pressure.
...