Pivotal altitude is the
height
Height is measure of vertical distance, either vertical extent (how "tall" something or someone is) or vertical position (how "high" a point is). For an example of vertical extent, "This basketball player is 7 foot 1 inches in height." For an e ...
for a given
ground speed
Ground speed is the horizontal component of the velocity of an aircraft relative to the Earth’s surface, also referred to as "speed over the ground". It is vital for accurate navigation that the pilot has an estimate of the ground speed that wil ...
at which the line of sight from the cockpit
directly parallel to the
lateral axis of the aircraft will remain stationary on an object on the ground. A good rule of thumb for estimating the pivotal altitude is to square the groundspeed, then divide by 15 (if the groundspeed is in miles per hour) or divide by 11.3 (if the groundspeed is in knots), and then add the mean sea level (MSL) altitude of the ground reference. The pivotal altitude is the altitude at which, for a given groundspeed, the projection of the visual
reference line to the pylon appears to pivot. The pivotal altitude does not vary with the angle of bank unless the bank is steep enough to affect the groundspeed.
United States Department of Transportation, Federal Aviation Administration, FAA-H-8083-3B, Airplane Flying Handbook
/ref>
A rule of thumb for calculating the pivotal altitude H in feet
The foot (: feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is an organ at the terminal part of the leg made up of ...
, given the speed in knots
A knot is a fastening in rope or interwoven lines.
Knot or knots may also refer to:
Other common meanings
* Knot (unit), of speed
* Knot (wood), a timber imperfection
Arts, entertainment, and media Films
* ''Knots'' (film), a 2004 film
* ''Kn ...
, is
:
References
Altitudes in aviation
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