Cruise Altitude & ATC

[benelong]

The test flight was at 4500' AGL. Are my Target Times calculated using 4500' as the cruise alt?

Normal cruise alt for my DHC4 Caribou is about 8000' so the climb and descent times are nearly doubled. Do I have to allow for that myself or have you taken it into account in the target time calculation?

Also is there any allowance for vectoring by ATC. I appreciate this is VFR but several of the airfields are controlled airspace or shall we just land and claim ignorance?

Thanks for all your efforts.

Benelong

[Andrew Godden]

Jan 2, 2009 20:34:01 GMT -5 benelong said:

The test flight was at 4500' AGL. Are my Target Times calculated using 4500' as the cruise alt?

Normal cruise alt for my DHC4 Caribou is about 8000' so the climb and descent times are nearly doubled. Do I have to allow for that myself or have you taken it into account in the target time calculation?

Also is there any allowance for vectoring by ATC. I appreciate this is VFR but several of the airfields are controlled airspace or shall we just land and claim ignorance?

Thanks for all your efforts.

Benelong

Benelong, et al,

This is a good question, particularly if you have not competed in the GAAR previously. For VFR flying and taking into account the expected weather, 4500 feet AMSL was considered a good average for the test flight. As your timing is based on overflying the Runway at YPKU and YARG, it obviously only provides an accurate calculation of cruise speed (which, of course, will vary at different altitudes) and without any affect from weather.

Your Target Time for each Flight Leg is based on this cruise speed and Leg distance and factors in components, based on an average, for the following phases of flight:
- take-off;
- climb: speed and distance; and
- circuit: speed and distance.

For the event, descent is considered to occur at cruise speed, and the circuit is based on a combined crosswind, downwind, base and approach of 12 nm, with a 5 nm approach.

Variables for weather and ATC are not included in the Target Time. The use of ATC adds a complete unknown, so, whilst some airports in the GAAR 2009 are controlled, they are treated as being uncontrolled for the purposes of the event. However, if participants want to use ATC that's also okay. Standard FS AI aircraft and any additional installed AI aircraft could also be a factor, particularly if they get in your way on 'finals' or 'short finals' - you don't want to become a statistic or the subject of an ATSB (Aussie safety authority) investigation.

Hopefully that answers your question and you might have to do some flight planning and pull out the old E-6B calculator. But knowing you, I am sure you already have it packed in your flight bag, along with a sufficient supply of 'Viagra Beer' - marketed and sold as VB, Victoria Bitter - and Barossa Valley Shiraz, hmmm, probably a 2005 vintage if my nose serves me well.

[Dave Evans bgak015]

Good answer,but I usally pled Ignorance, after three GAARs this seem to still work the best,and it fun to pop into the traffic pattern without the tower knowing were your going next.then hide amongst all the DC3s.