Glossary "P"


(1) Of balloon envelopes, stuffing the envelope into its storage bag after a flight. (2) Of balloon cold inflation, filling the envelope nearly full of cold air with a very large fan.

Parachute Top

A deflation system wherein the deflation port is sealed with a disc of balloon fabric shaped like a parachute. Lines attached to the edge of the parachute disc gather into a single line that may be pulled down by the pilot in the basket.

Pibal (Pilot Balloon Observations)

A small helium-filled balloon sent aloft to help determine wind direction, velocity, and stability.

PIC (Pilot in Command)

The pilot responsible for the operation and safety of an aircraft during flight.


(pronounced pee-ate'zo). A piezoelectric spark generator that is built into many modern balloon heaters to ignite the pilot light.

Pilot Light

A small, continuously burning flame used to ignite the main "blast" flame of a balloon heater.



Navigation by visual reference to landmarks.


Any small hole in a balloon envelope smaller than the maximum dimensions allowed for airworthiness.


A condition of the envelope fabric that allows hot air to escape. Excessive porosity requires increased fuel use and results in higher envelope temperatures.

Positive Control

"Control of all air traffic, within designated airspace, by air traffic control." (14 CFR part 1)


The engine or device that propels an airplane, airship, or rotorcraft. The term does not apply to balloons, which are considered to be unpowered aircraft.


All preparations, including gathering information, assembly, and inspection performed by the pilot before flight.

Pressure Relief Valve

A device in a propane tank designed to release excess pressure which may be caused by overfilling, overheating, or excessive nitrogen pressurization to prevent tank rupture.


Preventive Maintenance

Simple or minor preservation operations and the replacement of small standard parts not involving complex assembly operations.

Prohibited Area

"Designated airspace within which the flight of aircraft is prohibited." (14 CFR part 1)


A colorless and orderless gas. Ethyl mercaptan is added to propane to give it a detectable odor. Propane weighs 4.2 lbs. per gallon.

PTS (Practical Test Standard)

Book containing areas of knowledge and skill that a person must demonstrate competency in for the issuance of pilot certificates or ratings.

Pull Test

A strength test in which a section of envelope fabric is pulled to a definite pound measurement to determine if it meets the certification requirements for airworthiness.


An instrument used to measure air temperature inside the top of a balloon envelope.


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