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The value of a commonly understood traffic pattern altitude is obvious, but what is the history behind TPA of eight hundred feet in particular? Why not 700 or 900?

Was the later move to 1,000 AGL because of easy math only, or were there other reasons?

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    $\begingroup$ It's worth mentioning that 1,000' AGL might be popular for smaller aircraft, but at many airports 1,500' AGL is used for twins and turbine aircraft. Still I'm sure the answer will be fascinating if anyone has some research. $\endgroup$ – ryan1618 Feb 13 '16 at 14:29
  • $\begingroup$ Possible factors: Noise and view angle. Higher = less noise, lower = better view on the field. 800 ft may have been a good compromise at the time. With traffic and noise increase it could have been necessary to climb a bit. $\endgroup$ – mins Feb 13 '16 at 18:04
  • $\begingroup$ Possible duplicate of Why do some airports have a non standard traffic pattern altitude? $\endgroup$ – Jim Mar 7 '16 at 15:25
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The traffic pattern altitude (and the pattern turn direction) is set by the airport owner in coordination with the FAA. Refer to section 8.

Airport traffic patterns are often 1000 ft. AGL today. In recent past, the typical altitude above ground level was 800 ft. Flying Magazine, in a September 1958 article states:

Under VFR conditions proper entry into the zone is sadly neglected. Before you enter the control zone you should be at the Pattern Altitude which is more or less standard rule at every airport in the country--800 to 1,000 feet for light aircraft, 1,200 to 1,500 for heavy or fast aircraft. This provides you with altitude, yet gives plenty of room to make your turns. Letting down in traffic makes you vulnerable and blind, at the same time increasing the odds of hitting someone you will never see"

Experts and non-experts seem to agree an altitude increase would be beneficial:

  • Better noise abatement near the airport environment
  • Increasing tower heights
  • 1000 is easier to remember than 800

Fun facts:

  • Tangier island/KTGI airport elevation is 6 ft mean sea level. The traffic pattern altitude is 605 ft.
  • Truckee/KTRK is 5901 ft. MSL with an 1100 ft. TPA.
  • Sedona/KSEZ is 4830 ft. MSL. The TPA is 1173 ft.

Pilots flying into Sedona must be precise, haha!

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  • $\begingroup$ TGI has a restricted area above it at 700ft. The other two just even out the TPA to 7,000MSL and 6,000MSL, respectively. Not really a big deal $\endgroup$ – rbp Apr 7 '16 at 13:45
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    $\begingroup$ Maybe not a big deal but definitely one of those worthless aviation facts I'll never be able to forget. $\endgroup$ – PJNoes Apr 7 '16 at 15:36

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