With the powerful drive of ram air canopies capable of salvaging all but the most wayward of spots, there’s little reason why modern skydivers would want to take control and actually decide for themselves where they should be getting out.
This two-page feature article from Australian Skydiver magazine in 1972 focused on the niceties of learning to spot.
Then ASM editor and pioneer SA jumper Trevor Burns wrote the piece, aiming it a novice skydivers who, jumping old round canopies with extremely limited performance, were still very much at the mercy of the wind.
The cartoon, which illustrated the feature, first ran in the afternoon daily newspaper, The News. It was a humorous reference to the proximity of the old Two Wells Lion Park to the Lower Light DZ – and the Cunningham in question was jumper and News photographer Bob Cunningham.
The original article could probably now stand another run in ASM today, given that real spotting remains a mystery to many.
Interestingly, the recipe for a well-made drifter included a welding rod as a weight, taped on the end of a length of crepe paper – not advisable practice these days – but they were chucked out at demos all over Adelaide at one time.
And the reference to timing the drifter with your stopwatch is another throwback to a time when owning an altimeter was often still a sign of affluence.
Here’s how it used to be done.
Article from Australian Skydiver magazine, February 1972
And last week you
landed in the Lion Park
Some beginners, even some experienced jumpers, dread the responsibility of spotting themselves and others.
Like anything else it takes practice and everyone, even the pros, miss-spot occasionally.
When you get right down to the fundamentals, spotting is simple. Applying these fundamentals is not quite so simple.
Let's take it step by step and maybe you will learn enough to avoid having various parts of the DZ named after you.
Before you take-off check to see you have at least two drifters.It pays to have a spare. Brief your pilot to give you a run over the target at the planned opening height (for the sake of the exercise let's assume 2,000' ).
Tell him to make the run into the wind. Actually it does not matter which way the run is as long as the drifter is dropped directly over the target. But by running into the wind you reduce the aircraft's ground speed and cut out side drift thus making it easier to fly directly over the target.
Before starting the drifter run take one of the drifters and unroll the last two feet. When you throw it out it will now have an "instant tail" to help unroll it.
On the run into the target the pilot will lose sight of what is ahead of him. You will have to guide him with minor corrections. Get your signals sorted out with the pilot before you take-off.
In some aircraft you can simply talk. In others hand signals are necessary. Keep these precise and call corrections in terms of 5 or 10 degrees.
Unless the pilot is a complete knot head you should not need greater corrections than that. Instruct him to make flat or "rudder" turns only while approaching the target and to keep the wings level.
It's when the pilot banks the aircraft that the spotter becomes disorientated.
As you pass directly over the target have him power-off and then throw the drifter firmly down and backwards, punching your stopwatch as you do.
As the drifter falls away watch it continuously. You can easily lose sight of it against a mottled background.
Have the pilot bank to the right. If he can locate it himself and circle it, keeping it under his right wing tip, you should have no trouble seeing it too. When the drifter hits the ground, punch you watch again.
From 2000' a drifter should take about 2 minutes to reach the ground – give or take 10 seconds.
Now you can build your own airborne parallelogram. The streamer may be taken as you under an un-modified canopy, since it has been designed to fall at the same rate as an average man under an average canopy.
If the drifter landed half a mile east of the target you would want to open your canopy at 2,000', half a mile west of the target.
Simple isn't it? If you drop the drifter directly over the target and it takes exactly two minutes then every thing is simple. But, being human, we often drop the drifter a little to the left or right.
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| Trevor Burns spotting out of the Cherokee Six in the early 1970s and having a little fun with the slipstream. |
Right? Let's say the opening point you have computed is over a red roof shed. Now you know the drifter was 100 yards left of the target so your opening point will be 100 yards left of that shed.
The same theory applies if the drifter is thrown short or past the target. Let's assume the drifter took only one and a half minutes to land. Since it was in the air only three quarters of the time it should have been it could only have drifted three quarters of the distance it should have.
So, when you eyeball the distance from the drifter to the target and then an equal distance upwind you will really only be three quarters of the way to the opening point.
The whole picture becomes more complex if the drifter falls in one and a half minutes and was put out off the target. While a fast or slow drifter can be allowed for, it makes your job that much easier if it has the correct descent rate.
A true two-minute drifter can be made from a roll of crepe paper cut in half to give a streamer 10 inches wide and weighted at one end with a 10 inch long length of 10 gauge welding rod.
The color of the drifter is important too. If you are jumping in dairy country with nice, green grass everywhere a yellow or orange drifter is very easy to see as you circle. But if you are jumping over fields of ripened wheat or ploughed paddocks a yellow drifter will be almost impossible to spot. You would be better off with a black or dark colored streamer.
Always time every drifter you use. If you haven't a stopwatch the sweep hand of your wrist-watch will do.
Many beginner spotters make the mistake of using part of the airframe as a reference when lining up the jump run.
Assume you are using the trailing edge of the door as a sight. There you are, your head pressed against it sighting down to the ground.
What happens if the pilot happens to be climbing. You guessed. Your pre-determined exit point comes up and out you hop only to find yourself nearer the target than you wanted to be and all because you were looking at a point on the ground which was out in front of the aircraft.
If the aircraft is flying left wing low you will be looking at a point to the right of the flight path. Certainly you can tell your pilot to fly straight and level but that isn't always possible – the air may be turbulent.
A good jump pilot will always be climbing anyway. Straight and level flying is a waste of money in jump operations.
From high altitudes looking even a few degrees off the vertical may mean you are looking at a point several hundred yards away.
Learning to 'look straight down comes with experience. Get your head right out of that aircraft. Don't be timid. Personally, if it is possible I get one foot out on the step and get half out of the door while spotting.
The airframe is a trap. Don't be caught trying to use any part of it as a reference. As you bring the aircraft in on jump run, or drifter run for that matter use the only spirit level you have – the horizon. It's always level.
As you line up the aircraft glance at the horizon and then look quickly down every 10 seconds or so. You will quickly learn to look straight down as your eyeballs constantly bisect the horizon at right angles.
If you are going to jump and pull at 2,000' you will naturally leave the aircraft directly over the spot. But If you are jumping from 7,000' the exit point may not be above the planned opening point.
Freefall drift gives us another factor to consider. In the 30 seconds freefall from 7,000' a constant 60 mph wind will drift your body half a mile before opening.
Learning to allow for drift can only come with experience and from being constantly alert.
While you are on the ground watch others in the air. If you suspect a significant drift then talk to those who have just jumped. Once in the air look for signs of high upper winds.
Check out the speed and direction of cloud shadows on the ground. Constantly check out the door for drift in the aircraft's flight path across the ground.
This is the only time you may use part of the aircraft as a reference. Without proper instrumentation the best you can do is estimate the speed and direction of freefall drift and compensate for it accordingly.
Stay constantly alert and you will be surprised how accurate you became after a little experience. Happily for bad spotters all around the world there are two neat phenomena which have been described as "cones of maneouvrability".
These are the handy bandaids which help turn bum spots into dead centres. But more on these in the next issue.
For now just concentrate on eliminating those bum spots.
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