This Site is dedicated to all those families of the people that have tragically disappeared on flights in and around New Zealand. I only hope that from all the effort in building this site and from all the effort of those taking part in this venture, that it will bear fruit in bringing ‘closure’ to their memories!
Gavin Grimmer
One was that this particular Ryan had a higher cruise speed (probably rigged better) than the published designer’s cruise speed of 90 to 100 mph (and up to 110 if pushed!)
Another was that at the time they departed Richmond, Sydney, neither Hood nor Moncreiff had had any sleep in the previous 20 hours.
The Ryan had been modified having the second set of controls removed to make way for extra fuel tanks, and although the claim was that it was possible to change positions by climbing over the tank, in reality, when it was attempted, they found the plane became uncontrollable, so any further attempt at sharing the flying was abandoned.
I find that after flying for 4 to 5 hours at the controls, you get very tired, even after having a good nights sleep.
So here we have a pilot (Moncreiff), who has not had any sleep for 20 hours, taking off for a grueling flight of at least 12 (plus) hours across the Tasman, and in those days there was no such thing as an auto-pilot!
The weather was reported as there being a large anticyclone over the Tasman at the time and they would encounter a head wind (easterly) at the start of the flight, no wind as they crossed the centre of the anticyclone, and then a tailwind (westerly) for the rest of the flight.
It was calculated that the Ryan only had a ground speed of 90 mph due to the time taken from take off, to the time it was observed over the Trans-Tasman steamer “Maunganui”, off the coast of Sydney, but it needs to be remembered that it was at that point heavily laden with fuel, spent a lot of that time climbing,and was pushing into a headwind.
Moncreiff said that he would set the cruise rev of the motor at between 1600 to 1650 rpm as he felt that this would give them the fastest, most reliable, cruise, (between 100 to 110 mph) and as this was getting up towards the higher end of the accepted published cruise rev, I feel that given the forecast weather/wind conditions, it would be safe to calculate their ground speed as a minimum 105 mph.
Richmond, Sydney to Trentham, according to Google Earth is 1426 miles, so given a ground speed of 105 mph, they should have been overhead Trentham at just over 13 1/2 hrs flying, and given that they departed from Richmond, Sydney at 4.44am (NZ time) means that would have been at Trentham at around 6.14 pm (NZ time). As they were navigating on what was known as a “rhumb line”, this distance would have been four miles further and so this equates to about 6.16 pm, but as the actual wind speeds are not known to enable accurate calculations, then everything becomes a calculated guess anyway.
The expected arrival time at Trentham that evening was between 5.00 to 7.00 pm and the crowds waiting at Trentham had congregated there at this time expecting to see them arrive, so this shows that the calculated time above is reasonable.
The arranged radio signal was to be done every 15 minutes by locking the morse key down (held down by a screw) for a period of 5 minutes which would give a radio whine which would allow everyone listening, to know that they were still airborne, and hence safe. Unfortunately, they didn’t always get this whine out at the correct time, and this could be contributed to the extreme tiredness (and boredom) that Hood (the Radio Operator) would have been experiencing.
The last radio whine was heard at 5.22 pm, which means they were still airborne at that time.
At a ground speed of 105 mph, this gives them a distance traveled of 1326 miles…..right over the area the wreckage is believed to have been seen in Golden Bay!
From this calculated timing of their position, the mind boggles……It is very possible that the cessation of this signal indicated the cessation of the flight!!!
There is another possibility that they made landfall at Westport, as there were reports of people seeing an aeroplane at Tauranga Bay (7 ½ miles West of Westport), Denniston (10 miles East of Westport), and Karamea (about 46 miles north of Westport), and that would mean that it had to have traveled 1375 miles to Golden Bay which calculates to an average ground speed of 108 mph.