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
Find lost aircraft
HOME.
ZK-AFB.
ZK-EBU
ZK-BMP
find lost aircraft links
ZK-HNW
ZK-FMQ
ZK-CSS Cessna 172
ZK-ALT
ZK-AJV Tiger Moth
G-AUNZ
NZ278
NZ964
NZ332
NZ5517 Corsair
NZ5544 Corsair
NZ-WAC Piper Tomahawk
About Myself.
Sighting Reports.
NEWS 31 December 2008.
FORUMS.
GREAT BOOKS.
Additional info. to my book.
NEWS Dec 2009.
SITE MAP.
Buy My Book.
C O N T A C T.
Site Updates.

This site is kindly sponsored by:

Downloads.
NZ5544 Corsair
North Head Boeings.

An illustration of why refracted signals go further than the optical line-of-sight.

An illustration of tropospheric ducting. This system is more common with VHF radio signals

 

An illustration of a high-altitude tropospheric duct.

This system is more common with UHF radio signals and known as a “Skip”

 

ZK-CSS 10
ZK-CSS 10

Page 11 of 15

It would be more common for a VHF signal to travel north/south when it is caused by the setting sun as the hot/cooling air is at right angles to the sun, whereas we know that there was a southwesterly cold front coming up the coast at the time the Turner’s were flying. This would mean that a hot air inversion due to this, would allow the VHF signal to transmit in a northwest / southeast direction.

With Timaru being southeast of the Whataroa / Sealy Pass area, then I have no trouble believing that this is why Roy’s transmissions, especially his last transmission, could be heard on both sides of the Island at the same time.

Due to this phenomena, there is no requirement for the Turners to have been in “line of sight” of Timaru!   

Below is some illustrations showing how this can happen.

 

Next page.
Next page.