UPDATES TO THE SECOND EDITION
These have been incorporated into the current edition
Class C airspace
According to Carr Withall's update in the April/May 2005 edition of Sailplane
& Gliding, Class C airspace above FL195 will not be introduced in the UK until early 2006
at the soonest.
Added by John McCullagh 24 Mar 2005
How to steer a parachute
An emergency parachute is circular in shape after it is fully open but there are mesh-covered drive vents
located at the rear of the canopy that remove this symmetry. The drive vents make the canopy steerable and
create an air speed of about 10kph (depending upon body weight and altitude) in the direction you are facing.
The parachute has four risers (these are the straps that attach the harness to the canopy). You turn to the right by pulling
down the right rear riser by 15cm to 30cm (similarly for a left turn). The parachute will continue turning until
you stop pulling. It takes about 8 - 10 seconds to complete a full 360 degree turn. Try to land into wind. The following
link gives more information if you have Adobe Acrobat.
National Parachute Industries
Added by John McCullagh 30 Mar 2005
Practice PAN
You can practice making a call to get a position fix. Apparently they welcome the practice as well.
Tune to 121.5MHz and ensure that you have turned up the volume to hear what is being said. Listen for
2 minutes to ensure that a real emergency is not in progress. Transmit
"Practice PAN, practice PAN, practice PAN Glider your reg requires training fix". Wait for a response.
They should give you
a position relative to a major landmark. Give them feedback on the accuracy. They will ask if you need another service.
They can give you a magnetic heading to any airfield in the UK. Before you leave their frequency tell them to what frequency you
are changing back or they may assume that you are lost with a radio failure. The idea that you would pretend to practice when you really are lost should not have crossed
your mind.
Added by John McCullagh 30 Mar 2005
Why gliders speed up when contacting lift
You may have noticed that the ASI shows a speed increase when you fly into the core of a thermal.
The reason was first described by Dr AH Yates. An up-draught will increase the angle of attack because the airflow
comes more from below. Since the lift from the wings always
acts at right angles to the relative airflow (see the book), the lift acts further
forward and accelerates the glider.
Added by John McCullagh 5 April 2005
Typos
From where do they come?
Third para on page 10 - superfluous "you".
Superfluous "then" on page 11
There are bound to be more. Please let me know if you find others.
Added by John McCullagh 19 April 2005
New edition of Laws & Rules
The BGA have published a new edition (15th) of Laws & Rules. You can buy it or you can read it on-line in Acrobat format
http://www.gliding.co.uk/bgainfo/documents/Edition15final.pdf
Since I say that you should also read The Laws & Rules, I will not paraphrase all the changes.
However note that there are amendments in:
- Height for use of oxygen (FL100 as required by the law)
- Requirement to have a licence for any radio
- Approval of radio equipment
- Trailers (licencing of drivers, road-worthiness and inspection)
- How to park a glider
Added by John McCullagh 19 May 2005
Landing on a lake
This is a remote possibility, but there are three more points to make in addition to the one in the book about landing
parallel to the shore:
- If possible, land so that the wind will drift the glider into the shore
- Put the under-carriage down (this helps to slow the glider a little before the fuselage touches the surface)
- Shield your face as you touch down (it is possible that the sudden pressure of water will break the canopy)
Added by John McCullagh 7 June 2005
Beating the polar curve
The book describes how you can estimate your cross country speed from the polar curve. However you can beat this
apparent constraint by improving your glide angle. This is achieved by pulling up when passing through rising air
and by avoiding sink by following the "lines of energy" ie the paths that will take you the most lift and the least sink.
Added by John McCullagh 15 June 2005
Convergences
The book implies that the convergences coming from the north and south coasts of
Devon & Cornwall reinforce each other. They do not, they cancel each other out.
Added by John McCullagh 28 June 2005
The first "oops"!
The question on navigation on cross-winds gives a wind bearing 275 (almost westerly)
however the diagram in the answer shows a north-westerly. I meant the question to suppose a
north-west wind but somehow I typed 275 degrees. Try the question with a wind from 315
degrees.
Added by John McCullagh 2 August 2005
Avoiding collisions
Four more diagrams to illustrate why you need to look out all around. Look especially behind you and on the inside of the turn, but before you turn also look outside the turn (see diagram 2). While turning keep looking out (see diagram 3). Do not cut across ahead of another glider in a thermal, although the arcs are different lengths, the speeds can be different too.
Added by John McCullagh 24 August 2005
Updates to the first edition that have been included in the latest edition have now been archived but are still visible on
Updates to first edition
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