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I am reliably informed, that most Sonex cruise, with about 1.5 degrees nose up attitude.

Would´nt that depend of the airspeed you decide to cruise? The faster you go, the lower the aoa to keep the needle of the vsi on zero?

Skippydiesel wrote:I am reliably informed, that most Sonex cruise, with about 1.5 degrees nose up attitude.

Please site source. Thanks.

XenosN42 wrote:

Skippydiesel wrote:I am reliably informed, that most Sonex cruise, with about 1.5 degrees nose up attitude.

Please site source. Thanks.

Won't use his name (without permission), however Sonex plans builder & very experienced pilot in a wide range of piston aircraft (including Ag & airobats) who flew in a number of Sonex and went to the trouble of making some inflight measurements and found a consistent 1.5 degree nose up.

This is typical of what I see in slow cruise with the Aerovee.


In comparing the images, it's clear that my eye level is significantly higher.

Out of curiosity, I measured my pitch angle using the longeron as reference as 3.5 degrees at about 110-120mph at about 900lbs and about 3000ft density altitude.

Photos of the sight picture and relative angle of the longeron with the horizon taken doing 122kts this morning. To my eyes the longeron looks to be level with the horizon.

A couple of years ago I had made hard pink foam boosters that went over each side of the seat sling. They often broke in front, and also reduced stick motion because of interference with my legs from being higher. I've backed off the fronts, from about a half inch aft of the sticks. Seems better and I'll do a flight report when I get a chance. Each side has two layers so you can get a half or full inch boost.

Since my first post I did go up and take a closer look as well as bring up a digital level. As I recall, the level showed 3.3 - 3.4 deg and actually my nose was lower when straight and level than I thought, at least below the horizon.

Here are my foam boosters. They are cut and glued to match the seat pan bend. The top one is cut back further from the stick. Thickness is 9/16" each piece, so 1.125" total.

Bryan Cotton wrote:Here are my foam boosters. They are cut and glued to match the seat pan bend. The top one is cut back further from the stick. Thickness is 9/16" each piece, so 1.125" total.

Well that looks simple enough. I'll have to check my head clearance and see about a booster seat. Either that or a back-stretcher.