FAQs
On this page we try and answer the questions that have come in the course. Each week, as we work through the course, we'll update this page.
You might like to look over the questions from the previous years' courses which can be found here.
Part 1 - Introduction
Should the request for service be on the initial call or the full call?
It should be on the initial call. That is a) what it says in CAP413, b) what the controller wille expect and c) gives the controller a heads-up as to what you want.
What does 'discrete' mean when used with a radio frequency or transponder code?
For radio we mean a frequency that is not shared locally with other airfields. So not Safetycom or a Common Gliding Field Frequency which many clubs use. For transponder codes we mean an individually assigned code, rather than a conspicuity code such as 7000 or 2000.
Who can provide a Basic Service?
AFIS upwards - that means an Air Ground Communication Service (suffix 'Radio') can't.
Part 2 - The flight
Do I need to use the words 'altitude' and 'QNH' when reporting my level/altitiude (for example in the full message)?
For the test, it's worth doing. It's not wrong and it is unambiguous. CAP413 chapter 3 Page 2 applies.
In real life, the key is to be unambiguous. Do it on the first conversation with ATC. After that, once you've agreed what you're using (eg altitude and the QNH, or height and QFE in some cases) you can report just using the number. CAP413 does give one or two examples of an altitude without using the word (eg 6.88 on pdf p47)
Generally you should fly cross country with the correct QNH set and report your altitude - flying with your local airfield QFE is not helpful for this.
Where does the callsign come with 'Traffic not sighted' or 'Traffic in sight'?
I'm not sure it matters very much. I'd probably put the callsign on the end if I was responding to ATC's traffic report, and on the beginning if (a bit later) I was initiating a new call to tell them. But you can see examples of both in CAP413 (eg 5.25 on pdf p15, and 4.36 on pdf p20).
Part 3 - The flight (continued)
Can you remind me about the various altimeter settings?
QFE: altimeter shows your height above an airfield. Typically what glider pilots use when flying locally. Much less good for cross country.
QNH: altimeter shows altitude - ie height above mean sea level (AMSL). It will change with time and as you travel across the country.
Standard Pressure Setting (1013.2 hPa): altimeter shows Flight Level. Useful if you're flying close to airspace with a level defined using Flight Levels. IFR traffic uses this above the Transition Altitude (typically between 3000 and 6000 ft in the UK), and sets QNH below the Transition Level.
Regional Pressure Setting (RPS): Used by British (not American) military controllers (so you'll probably get it if you ask for a service from, eg, Benson, Wittering, Marham etc). It's the lowest forecast QNH for an area, forecast an hour ahead. The areas have names (eg Wessex, Cotswold and so on) and can be seen on a 500K map. It will likely be lower than the actual QNH and your actual altitude will be a bit higher than the altimeter suggests. It's used so that military aircraft flying low level can set their altimeter and be confident that the ground won't be higher than they expect. There's a gotcha though. If you set the RPS, and fly close to a airspace floor defined by an altitude, you can accidentally infringe. In practice it's not very useful for glider pilots, but you might get given it and you should understand what it is.
My view is that glider pilots should fly on QNH during a cross country flight, and adjust it as and when it changes. Personally, I take off and land my glider using QNH too - that way I don't have to remember the QFE or adjust the altimeter when I return. However, I do have to remember to take the airfield elevation into account.