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In the UK, aerodrome weather information includes not only QNH (the air pressure at mean sea level), but also QFE, the air pressure at runway level. To arrive at an aerodrome, normally one obtains and sets the altimeter to QFE, so that it reads height above aerodrome level. Then if the circuit (traffic pattern) height is 1000 ft (which it usually is), you just read 1000 ft on the altimeter all the way around the circuit; for a standard overhead join it says 2000 ft; and so on. At any aerodrome the altimeter reads the same thing, because you always set QFE.

I've heard that QFE is not used in the US. Do you just have to work out the circuit height in your head by adding 1000 ft to the published aerodrome level? Or are circuit heights given amsl?

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  • $\begingroup$ @Jim I didn't find the linked question incredibly helpful, because the question and answers are written with a lot of assumed knowledge about US procedures and terminology. In addition, one of the upvoted answers to this question would make no sense at all on the other question. $\endgroup$ – Dan Hulme Feb 11 '16 at 16:42
  • $\begingroup$ The questions are essentially the same. It does not matter that the answers are different. Different people will not necessarily answer identically. $\endgroup$ – Jim Feb 11 '16 at 17:50
  • $\begingroup$ My point isn't that the answers are different: it's that a good answer to one question doesn't answer the other question at all. I think that means the questions can't be duplicates, even though they're similar. $\endgroup$ – Dan Hulme Feb 11 '16 at 17:51
  • $\begingroup$ If you are referring to SentryRaven's answer the information he provided is irrelevant to both questions. FAA sectional charts do not depict traffic patterns. $\endgroup$ – Jim Feb 11 '16 at 18:14
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The Airport/Facility Directory (AFD) has that info. It lists the Traffic Pattern Altitude (TPA) in both MSL and AGL, as well as circuit direction.

QFE is not used in the US. So yes, you have to make the correction for field elevation. For example, an airport at 1200 MSL would have a pattern altitude of 2200 ft. (1000 AGL for props. 1500 AGL for Jets) and would be flown using that altitude on the altimeter.

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  • $\begingroup$ Thanks for confirming that. Which of the two cases at the end of my question is true? i.e. does the runway information include a "circuit altitude amsl" entry, or do you just do the addition yourself when planning the flight? $\endgroup$ – Dan Hulme Oct 11 '15 at 16:26
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    $\begingroup$ You add the addition yourself. $\endgroup$ – wbeard52 Oct 11 '15 at 19:19
  • $\begingroup$ The Airport/Facility Directory (AFD) has that info. It lists the TPA in both MSL and AGL. As well as circuit direction. $\endgroup$ – compilotrc Oct 12 '15 at 14:03
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The same basically applies to Europe. QFE is mostly used by glider pilots, whereas powered aircraft use QNH settings. Most visual approach charts or airport charts have the pattern altitude indicated at the visual representation of the pattern, at airports where no pattern altitude is provided or depicted, you use the rule of thumb to add 1000ft to the airport elevation.

Below image shows the pattern altitude at Cottbus-Drewitz, where the airport elevation is 274ft but the pattern altitude is 1100ft MSL and the other image the pattern at Lauenbr├╝ck, where the airport elevation is 76ft, but no pattern altitude is given. The calculated pattern altitude would be 1100ft (76ft rounded to 100ft + 1000ft). Flugplatz Drewitz Pattern (Image Source: www.flugplatz-drewitz.de - Pattern with Altitude in MSL) Flugplatz EDHU Pattern
(Image Source: www.edhu.de - Pattern without Altitude - Airport ELEV 98ft)

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  • $\begingroup$ Sorry, I meant to respond to the OP, not you're comment. $\endgroup$ – compilotrc Oct 12 '15 at 14:03
  • $\begingroup$ -1 this does not answer the OP's question. $\endgroup$ – Jim Feb 11 '16 at 18:09

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