From: Douglas Brunner [mailto:legacyflyer@gmail.com]
Sent: Friday, February 28, 2014 7:33 PM
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Subject: RE: Flap Hinge Fairings
I was hoping that these flap hinge fairings were going to make me a small fortune in aviation (you know, the kind that starts with a large fortune) but ….
Before Flap Hinge Fairings | | | | |
| | | | | | |
Heading | | Ground Speed | True Air Speed | Date 2/25/14 | |
| | | | | | |
360 | | 232 | 234 | Alt | 8,000 | ft |
| | | | OAT | 55 | Deg. F |
90 | | 262 | 234 | RPM | 2,600 | |
| | | | MAP | 23.3 | inches |
180 | | 247 | 234 | Fuel Flow | 18.2 | GPH |
| | | | Peak EGT | 1,295 | Deg. F |
270 | | 216 | 234 | EGT | 1,195 | Deg. F |
| | | | | | |
| | 239 | 234 | | | |
| | | | | | |
Flap Hinge Fairings Installed | | | | |
| | | | | | |
Heading | | Ground Speed | True Air Speed | Date 2/28/14 | |
| | | | | | |
360 | | 235 | 237 | Alt | 8,000 | ft |
| | | | OAT | 48 | Deg. F |
90 | | 250 | 237 | RPM | 2,600 | |
| | | | MAP | 23.4 | inches |
180 | | 243 | 237 | Fuel Flow | 18.4 | GPH |
| | | | Peak EGT | 1,295 | Deg. F |
270 | | 231 | 237 | EGT | 1,195 | Deg. F |
| | | | | | |
| | 240 | 237 | | | |
Using 4 way GPS ground speed - It appears that they give about 1 knot in speed improvement. And given all the factors at play and the possible variation in the measurements, it is possible they don’t even do that.
Using True Air Speed from my Chelton, they appear to give an improvement of 3 knots. However, I don’t believe this is as accurate or reliable a measurement as the GPS ground speed.
I will also say that the fitting and body work I did to install them was quick and dirty and could be improved on. So maybe the 1 knot will turn into 2 but …..
Subjectively, I thought they improved my climb rate - which would make sense given what parts of the wing would be in the air stream with a positive angle of attack. However, I don’t have any data to back up this subjective impression.
I can make sets for people that want them. Probably, the most economical way to get them would be with a group order. One off 3D printing can also be done but will probably cost more. I will approach various suppliers to get estimates.
If you are interested contact me off the LML at: legacyflyer@gmail.com