Gavin Grimmer
In the meantime, he would have initiated a 30 second rate one turn (3 degrees per second) to the left to at least start heading in the general direction, and once established on this heading he would have less pressure giving him time to make a more accurate calculation of the correct heading to Singleton. This 90 degree turn would have put him close to the track for West Maitland had it not been for the crosswind. I believe (and the calculations tend to confirm this) Mike had worked out a heading allowing for the wind and was already turning towards this heading when he was told (09:30:01), “MDX, Vector to West Maitland – maintain present heading.” He would then believe the heading shown on his compass at that time was the heading with the wind drift 'built in' for West Maitland. The only problem was it was the heading he had just turned away from that Sydney Radar were meaning, but due to Sydney only getting a 'paint' every twelve seconds, they did not have enough information to show that he had already turned to another heading... a classic case of a misunderstanding!
To demonstrate this, I have calculated the continuing track and rate one turn radius from the Radar Ident position allowing for a reaction time after being told his position (now you know why I wanted the direction he was heading at the time of Ident) and added red pointers showing where each 12 second radar paint would have appeared.
Note the pointers 4, 5, 6, and 7 are in the direction of West Maitland and the radar operator would have needed at least 3 paints to get an idea of the direction. Note the No. 8 pointer is part way in the turn.
In this image on the right it shows the track to Singleton. Note also that pointers 4 to 9 would all look to the radar operator as though they were on a general heading.
With a 240/76 knot wind that Mike thought he was in, he would have to have had a magnetic heading of 193° to make good the track to Singleton (24° drift) and yet when he was asked one minute and 17 seconds later his heading (as a result of observing that he had turned southwards), Mike said he was averaging on a heading of somewhere around 220.
I believe the “220” was derived not as a result of just glancing at his compass, but from his calculation sheet, in other words he was trying to hold a steady heading of 220 (with difficulty)... and not just 'happened' to be flying in that direction.
You need to remember that he was a very experienced Air Force Navigator (4400 hrs), and at this point of my research, at 09:29:42 when he asked for a Vector to West Maitland, it appears he had no intention of going to West Maitland... he only wished to get a bearing on West Maitland to confirm which direction it was in! 220° can be explained as Mike knowing that the difference between the tracks to West Maitland and Singleton was 24°, so 193 + 24 = 217 plus an extra couple of degrees = 220... an old navigator's trick.... If you track exactly on course and you are off track, when you get to your destination and can't see it, then you are faced with a dilemma... is it to your left or right? Whereas with a few extra degrees flown to one side of the track – in this case to the right – then you would know that it is somewhere to the left.
A course a little further towards the west was also a safer option in case the wind grew stronger as I’m sure it is known to do over this stretch being a bit like a corridor for the wind to funnel through. It’s kind of on par with what happens in our Cook Strait in this Country. It’s easy to drift back on line with the wind than have to ‘fight’ going in to it.
MDX pg 14
