When at Taree, by dialing in the frequency on the ADF to Singleton (290 Mhz) and setting the course to 239 + 1 (240°T) – to bring it directly into wind, then adding another 6° (246°T) to give a further allowance of distance from the zone, this then would have given them a margin of error to stay clear. Of course an ADF is in 'Magnetic' (minus 11° in this case) but I have explained it as “True” to make it easier to explain.
The “37” would be just a reminder that there was another 37 nm to run to get to Singleton after intercepting the Mt Sandon radial. The offset to a 240/40 forecast of 6° would give an extra 1° giving a total of 8°. Taree to Craven is in fact 12° but there was no real reason for Mike to have flown exactly to that course. 8° would place them only 3 nm away from RP Craven so there was nothing in it (and it meant a slightly quicker time to get back to Bankstown).... cutting the corner!
Now all we have to do is apply this information to where MDX was first picked up on radar...
It has been generally excepted that Mike had got confused with the frequencies of Singleton (290) and Scone (209) and had tuned into Scone by mistake – an easy mistake to make when under pressure. Most (if not all) believe this was dialed in at RP Craven, but from observing my previous plot prior to this one, it now becomes apparent that this happened at Taree. So now 'armed' with this knowledge, we will put this into the equation and see how it fits:
Taree to Scone = 264°T + 6° drift = 270°T.
270°T with a wind speed of 240/50 kts (Cessna 206 VH-AZC) = 9° drift = 279°T
From the point Mike thought he was 33 nm away from Craven only alters the course from Taree to Singleton by about 1 degree so 279°T is still a good course to use. (We will never get it that precise for it to matter).
When he intercepted the Mt Sandon radial, he would have just turned and flown directly towards the beacon as the drift in 37 nm would have been negligible – he would have expected only a matter of 3° maximum in a southerly direction.
In this area, he would have experienced a 5 drift in a northerly direction and you'll note the position in this image above shows him to the north but it is only 2°.
If you go back to my previous calculations, you'll see that I believed the point he crossed the radial was a little further down the radial and when you consider that an ADF course flown without the correct allowance for drift will result in what is known as a parabolic curve, so by using this second method as above to try to determine the course flown results in virtually the same conclusion – Mike crossed the radial somewhere in this region of the radial as shown previously, and again on the next page...
MDX pg 10