Pitot Static Systems

Introduction:

Pitot Static systems measure and compare air pressures from the Pitot tube [Figure 1] and static port [Figure 2]
These measurements are typically used to display indications for the Airspeed Indicator (ASI), Altimeter, and Vertical Speed Indicators (VSI)
- May be heated to provide protection from ice build up
Consists of two components:

Pitot Tube
Static Port

Pitot Tube:

Pitot Tube
Invented by Henri Pitot in 1732
Placed in front of airfoil to prevent disturbed air from entering
Used only for the Airspeed Indicator (ASI)
Pitot Heat:
- Pitot Tubes are often electrically heated which can prevent, and remove ice accumulation
- Note that these devices should only be utilized during ground operations when necessary
  - Leaving them on unnecessarily can cause heat to the point of damage/malfunction

Static Port:

Static Port
Samples ambient still air atmospheric pressure
Normally flush mounted on the side of the aircraft where air is undisturbed
Senses movement of the aircraft through air both horizontally and vertically
Placed in one more more places where the air is not disturbed
Some ports are heated
Dual ports remove errors due to slips and skids
Responsible for Airspeed Indicator, Altimeter and Vertical Speed Indicators
The POH/AFM contains any corrections that must be applied to the airspeed for the various configurations of flaps and landing gear
Instrument Flying Handbook, A Typical Electrically Heated Pitot-Static Head
Instrument Flying Handbook, A Typical Electrically Heated Pitot-Static Head
Static Port

Pitot-Static System Malfunctions:

Blockages in the system can cause a variety of errors
To prevent these errors you must complete a thorough pre-flight
Blockages can occur from FOD, striking an object, insects, and icing
Consult the Pilot's Operating Handbook/Airplane Flight Manual (POH/AFM) to determine the amount of error
Pitot0Tube Blockage (static open):
- At the altitude where the Pitot tube becomes blocked, the airspeed indicator remains at the existing airspeed and doesn't reflect actual changes in speed
  - At altitudes above where the Pitot tube became blocked, the ASI displays a higher-than-actual airspeed increasing steadily as altitude increases
  - At lower altitudes, the ASI displays a lower-than-actual airspeed decreasing steadily as altitude decreases
Pitot-Tube Drain Hole Blockage:
- Would cause ASI to malfunction
Pitot-Tube and Drain Hole Blocked:
- Would cause ASI to malfunction
Static Port Blockage:
- Would cause ASI, altimeter, and VSI to malfunction
- If in a real emergency, malfunctions can be corrected with alternate air or breaking the glass on a Pitot static instrument (VSI)
- If the static ports become blocked, the ASI would still function but could produce inaccurate indications
- At the altitude where the blockage occurs, airspeed indications would be normal
  - At altitudes above which the static ports became blocked, the ASI displays a lower-than-actual airspeed continually decreasing as altitude is increased
  - At lower altitudes, the ASI displays a higher-than-actual airspeed increasing steadily as altitude decreases
- The trapped pressure in the static system causes the altimeter to remain at the altitude where the blockage occurred
- The VSI remains at zero
- On some aircraft, an alternate static air source valve is used for emergencies
- If the alternate source is vented inside the airplane, where static pressure is usually lower than outside static pressure, selection of the alternate source may result in the following erroneous instrument indications:
  1. Altimeter reads higher than normal
  2. Indicated airspeed (IAS) reads greater than normal
  3. VSI momentarily shows a climb

Common Training Aircraft Pitot-Static System Characteristics:

Piper Arrow:
- Composed of a heated Pitot tube on the lower left wing
- Two static ports are located on each side of the fuselage
- Alternate static air (below pilot control yoke) provides static pressure from inside the cabin
Cessna 172:
- Composed of a heated Pitot tube on the lower surface of the left wing
- An external static port is located on the lower left side of the forward fuselage
- Pitot Tube consists of a heating element, a 5-amp switch/breaker, and associated wiring
- Alternate static (below throttle) provides pressure from inside the cabin

Private Pilot - Operation of Aircraft Systems Airman Certification Standards:

To determine that the applicant exhibits satisfactory knowledge, risk management, and skills associated with the safe operation of systems on the airplane provided for the flight test
References: FAA-H-8083-2, FAA-H-8083-3, FAA-H-8083-23, FAA-H-8083-25; POH/AFM
Lesson Plan

Operation of Aircraft Systems Knowledge:

The applicant must demonstrate an understanding of:

PA.I.G.K1:
Airplane systems, to include: (Note: If K1 is selected, the evaluator must assess the applicant's knowledge of at least three of the following sub-elements
- PA.I.G.K1a:
  Primary flight controls
- PA.I.G.K1a:
  Secondary flight controls
- PA.I.G.K1c:
  Powerplant and propeller
- PA.I.G.K1d:
  Landing gear
- PA.I.G.K1e:
  Fuel, oil, and hydraulic
- PA.I.G.K1f:
  Electrical
- PA.I.G.K1g:
  Avionics
- PA.I.G.K1h:
  Pitot-static, vacuum/pressure, and associated flight instruments
- PA.I.G.K1i:
  Environmental
- PA.I.G.K1j:
  Deicing and anti-icing
- PA.I.G.K1k:
  Water Rudders
- PA.I.G.K1l:
  Oxygen Systems
PA.I.G.K2:
Indications of and procedures for managing system abnormalities or failures

Operation of Aircraft Systems Risk Management:

The applicant demonstrates the ability to identify, assess and mitigate risks, encompassing:

PA.I.G.R1:
Failure to detect system malfunctions or failures
PA.I.G.R2:
Improper management of a system failure
PA.I.G.R3:
Failure to monitor and manage automated systems

Operation of Aircraft Systems Skills:

The applicant demonstrates the ability to:

PA.I.G.S1:
Operate at least three of the systems listed in K1a through K1l above appropriately
PA.I.G.S2:
Use appropriate checklists properly

Private Pilot - Systems and Equipment Malfunctions Airman Certification Standards:

To determine that the applicant exhibits satisfactory knowledge, risk management, and skills associated with system and equipment malfunctions appropriate to the airplane provided for the practical test and analyzing the situation and take appropriate action for simulated emergencies
FAA-H-8083-2, FAA-H-8083-3; POH/AFM

Systems and Equipment Malfunctions Knowledge:

The applicant must demonstrate an understanding of:

PA.IX.C.K1:
Partial or complete power loss related to the specific powerplant, including:
- PA.IX.C.K1a:
  Engine roughness or overheat
- PA.IX.C.K1b:
  Carburetor or induction icing
- PA.IX.C.K1c:
  Loss of oil pressure
- PA.IX.C.K1d:
  Fuel starvation
PA.IX.C.K2:
System and equipment malfunctions specific to the airplane, including:
- PA.IX.C.K2a:
  Electrical malfunction
- PA.IX.C.K2b:
  Vacuum/pressure and associated flight instrument malfunctions
- PA.IX.C.K2c:
  Pitot/static system malfunction
- PA.IX.C.K2d:
  Electronic flight deck display malfunction
- PA.IX.C.K2e:
  Landing gear or flap malfunction

PA.IX.C.R1:
Failure to use the proper checklist for a system or equipment malfunction
PA.IX.C.R2:
Distractions, loss of situational awareness, or improper task management

Systems and Equipment Malfunctions Skills:

The applicant demonstrates the ability to:

PA.IX.C.S1:
Describe appropriate action for simulated emergencies specified by the evaluator, from at least three of the elements or sub-elements listed in K1 through K5 above
PA.IX.C.S2:
Complete the appropriate checklist

Conclusion:

Still looking for something? Continue searching:

Pitot-Static Systems

Introduction:

Pitot Tube:

Pitot Heat:

Static Port:

Pitot-Static System Malfunctions:

Pitot0Tube Blockage (static open):

Pitot-Tube Drain Hole Blockage:

Pitot-Tube and Drain Hole Blocked:

Static Port Blockage:

Common Training Aircraft Pitot-Static System Characteristics:

Piper Arrow:

Cessna 172:

Private Pilot - Operation of Aircraft Systems Airman Certification Standards:

Operation of Aircraft Systems Knowledge:

PA.I.G.K1:

PA.I.G.K1a:

PA.I.G.K1a:

PA.I.G.K1c:

PA.I.G.K1d:

PA.I.G.K1e:

PA.I.G.K1f:

PA.I.G.K1g:

PA.I.G.K1h:

PA.I.G.K1i:

PA.I.G.K1j:

PA.I.G.K1k:

PA.I.G.K1l:

PA.I.G.K2:

Operation of Aircraft Systems Risk Management:

PA.I.G.R1:

PA.I.G.R2:

PA.I.G.R3:

Operation of Aircraft Systems Skills:

PA.I.G.S1:

PA.I.G.S2:

Private Pilot - Systems and Equipment Malfunctions Airman Certification Standards:

Systems and Equipment Malfunctions Knowledge:

PA.IX.C.K1:

PA.IX.C.K1a:

PA.IX.C.K1b:

PA.IX.C.K1c:

PA.IX.C.K1d:

PA.IX.C.K2:

PA.IX.C.K2a:

PA.IX.C.K2b:

PA.IX.C.K2c:

PA.IX.C.K2d:

PA.IX.C.K2e:

PA.IX.C.K2f:

PA.IX.C.K3:

PA.IX.C.K4:

PA.IX.C.K5:

Systems and Equipment Malfunctions Risk Management:

PA.IX.C.R1:

PA.IX.C.R2:

Systems and Equipment Malfunctions Skills:

PA.IX.C.S1:

PA.IX.C.S2:

Conclusion:

References: