Oh yes, I remember -that- flight very well indeed. What impressed me the most was the short (to me) time between cloud transitioning from 'towering Cu' to 'embedded Cb'.
Dennis M. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Texler, Michael Sent: Friday, 2 March 2007 17:30 To: Discussion of issues relating to Soaring in Australia. Subject: [Aus-soaring] Lightning and flying. There was a special about lightning on the ABC last night, did anyone watch it? Much of it waffled on, but there was some spectacular footage taken from insight a research fighter jet that flew inside a Cumulonimbus (Cb) for the sole intention of being struck by lightning (to research its effect upon aircraft). Plus footage of a jumbo jet being struck by lightning shortly after takeoff. I know that there has been the oft quoted lightning strike to an ASK21 in England resulting in an aircraft breakup inflight (with both occupants parachuting to safety, thus opening up the "do we or do we not wear parachutes" on training flights debate). http://www.pas.rochester.edu/~cline/ASK%20lightning%20strike/ASK%20accident% 20report.htm Embedded Cb are particularly troublesome, i.e. whereby there is an overcast with the storm cells embedded within the cloud layer. The only indication that an active storm is present is when you start seeing the lightning coming out of a smooth cloud-base along with precipitation. I recall one day when flying in a friendly comp from AUGC Lochiel airfield in a wooden aircraft, an ES59 Arrow (28th Feb 1999). It was a hot day with rough scratchy thermals, but then the day took off. Towering Cu's formed around the task area after we had all left on task. I was heading to Crystal Brook (about 60km from home) when the day became overdeveloped, cloudbase was 9,000' and the lift had been working well. Then there were reports of hail falling near Brinkworth, hence the task was abandoned and we all went running for home. I was at Crystal Brook at 8,000' and then followed under a wide, dark, flat bottomed cloud street back home, actually gaining height in straight line flight, it got to the point that I had to deploy full airbrake and fly at max rough air to prevent going up. I could see microbursts hitting the ground east of track north of Snowtown. Dennis Medlow was in front of me in Boomerang QZ and can vouch for the conditions. Soon after, there were two lig! htning bolts either side of my intended path, hence I immediately altered course 90 degrees to the right heading towards the blue sky west of the cloud. Once in the blue and looking back at the cloud was an impressive line of Cb's embedded in a mid-level overcast stretching from the Adelaide plains to the Southern Flinders Ranges. I managed to cover 120km in less than 2hours, with an average speed of 80km/h in the ES59 Arrow. A memorable be somewhat unnerving flight. I am sure that many subscribers on this list have their own lightning/Cb related story. _______________________________________________ Aus-soaring mailing list [email protected] To check or change subscription details, visit: http://lists.internode.on.net/mailman/listinfo/aus-soaring _______________________________________________ Aus-soaring mailing list [email protected] To check or change subscription details, visit: http://lists.internode.on.net/mailman/listinfo/aus-soaring
