I talked to Ken, advised that the current descent profile is too agressive. A normal glide for an approach ( at lower sirspeed ) is a 3 degree angle. However, at higher speeds, this becomes a bit hard on the ears. A good formula is to take 1/2 your groundspeed in knots, add a zero to it, and that is the required rate of descent to maintain a 3 degree glide. For example, an RV cruises at about 160 knots, and descends at about 175+ knots, that equates to about 800-900 feet per minute to hold a 3 degree glide, therefore, a 2 degree glide is much easier on the ears and is compatible with the performance of most experimentals. Also, for most RV's and similar aircraft, a descent profile of about 5 miles per 1000' feet works quite well. I REALLY hope Advanced adresses the verticle navigation, and also comes up with a "green bannana" indicating where on the map the top or bottom of the verticle profile will be reached, just like all the other EFIS manufactures. Having gone through the growing pains and doing beta testing for Blue Mountain ( similar fate of the DoDo bird) I am anxious for these features to work as advertised to enhance Advanced market share and survivability. BTW, for those who like formulas, another method to compute a 3 degree glide is to take the distance to touchdown and multiply it by 3, and the result should be the altitude above touchdown, i.e. 5 miles from the runway, 1500 AGL, 9 miles = 2700 AGL, sink rate needs to be 1/2 the ground speed plus a zero, i.e. 100 knots - 500 feet per minute, works real good, lasts a long time! Regards,
Gary Brown ATP A&P I.A. CFI DAR (Continental Airlines - Retired)
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