Guy Buchanan
Joined: 16 Jul 2006
Posts: 1204
Location: Ramona, CA
|
 Posted: Fri Sep 22, 2006 7:16 am Post subject: Flight Test Data |
 |
|
I'd like to get some criticism of the following flight test data:
Max speed - 90 MIAS (at) 6700
Cruise - 78 MIAS (at) 5800
Vx - 54 MIAS (5500' DA. Does Vx or Vy vary with DA?)
Vy - 59 MIAS
Vs0 - 35 MIAS
Vs1 - 42 MIAS
Power on stall, no flaps - 35 MIAS
Power on stall, full flaps - 26 MIAS
Minimum rate of descent is just above stall speed, clean or dirty with the
minimum RoD = -425fpm (at) 45 MIAS clean and -390fpm (at) 40MIAS dirty. I had to
guesstimate a minimum angle of descent. The curve is very flat from stall
to a local max somewhere near 55 MIAS. (I.e. max glide is near 55 MIAS.)
Interestingly the glide ratio is slightly better with half flaps at 45 MIAS
with indications of even better performance at slower air speeds. (Stall's
at about 42 MIAS.) And it has 90fpm less sink rate! So it looks like the
ideal engine out glide is 45 MIAS at half flaps downwind or no-wind and 55
MIAS no flaps upwind. (See chart.)
Now I know my plane is dirty. I have a 10" spinner, but a lot of excess air
is going through the cowl. (I have the ~13 x 2.5" exit.) I also have the
radiator in the breeze, dropped 1" from the lower fuselage surface, mainly
to enhance cooling on the ground. Thus I suspect I can eliminate almost 1
square foot of drag area between the two. (I'm not sure how much speed that
will give, but it represents almost 15% of the total drag. I'm estimating
that's good for about 5 MIAS.)
Guy Buchanan
K-IV 1200 / 582-C / Warp / 100% done, thanks mostly to Bob Ducar.
| | - The Matronics Kitfox-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
| Description: |
|
| Filesize: |
79.69 KB |
| Viewed: |
160 Time(s) |
|
_________________
Guy Buchanan
Deceased K-IV 1200
A glider pilot too. |
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
