Kitfox service advisory 27. |
|||||||||||||||||
|
|||||||||||||||||
|
|||||||||||||||||
|
|
|||||||||||||||||
| Kitfox instrument installation, pitot and static tube placement. | |||||||||||||||||
|
SERVICE
LETTER # 27 DATE:
May 1, 1994 SUBJECT:
Airspeed Indicators, Pitot/Static System TO:
All Kitfox Owners FROM:
SkyStar Aircraft, Engineering Division The
engineering department at SkyStar has been conducting flight tests on
various Kitfox models using a pitot/static test boom.
We have found that there is a broad variation in the atmospheric
pressure differences between those measured by the test boom and those
inside the cabin. This is
important in that many Kitfox's are flying with their flight instrument
static ports open to cabin air pressure.
These pressure differences vary with changing conditions such as
cabin air vents being open or closed, the effectiveness of the door
seals, amount and installation of the upholstery, varying airspeeds,
etc. All of these factors
represent certain degrees of inaccuracy of the primary flight
instruments; airspeed
indicator, altimeter, and vertical speed indicator, and the transponder
altitude encoder, if installed. To
reduce or eliminate these inaccuracies, we have developed and are
strongly recommending the installation of a fuselage mounted static
port. Other
factors can result in instrument inaccuracies, and you should try to
eliminate these as well: long
term storage; improper
handling; improper
installation; defective
components; and general
wear and tear. We
recommend that you have your pitot/static system tested by a qualified
technician, using standard shop test equipment.
This is required by FAR 91.411 every 24 calendar months if you
fly IFR or if you have installed a transponder with altitude encoder. AIRSPEED
INDICATOR MARKINGS VNE
Never exceed speed is the speed limit that may not be exceeded at
any time. It is indicated
by the red line on the airspeed indicator. VNO
Maximum structural cruising speed is the speed that should not be
exceeded except in smooth air, and then only with caution.
It is indicated at the junction of the green and yellow arcs. VFE
Maximum flap extension speed is the highest speed permissible
with the wing flaps in the prescribed extended position.
It is indicated by the top of
the white arc. VS1
Stalling speed is the minimum steady flight speed at which the
aircraft is controllable with the flaps up, and the power off at gross
weight. It is indicated by
the bottom of the green arc. VSO
Stalling speed (landing configuration) is the minimum flight
speed at which the aircraft is controllable with flaps in the landing
configuration, power off and at gross weight.
It is indicated by the bottom of the white arc. NOTE:
THE TWO STALLING SPEEDS, VS1
AND VSO, CAN ONLY BE DETERMINED BY ACTUAL FLIGHT TEST OF EACH INDIVIDUAL
AIRCRAFT. You,
as the builder/manufacturer, are responsible for determining the flight
envelope of your aircraft. The
flight test phase for your aircraft is where this is determined. AC90-89
(Amateur-Built Aircraft Flight Testing Handbook) will guide you through
these steps. This book can be obtained through SkyStar.
The flight testing will give you the information you need to mark
your airspeed indicator properly. Below
are the airspeeds for a Kitfox, built per the manual.
Stall speeds and rate of climb speeds are not given and can only
be determined by actual flight testing.
*NOTE:
VNE may
be extended to 100 MIAS if the flaperon mass balance weights are
installed. All speeds are
given in Miles per hour Indicated Air Speed (MIAS). You
can have your airspeed indicator marked on the dial face by an aircraft
instrument repair shop or mark the glass face with colored decals. Please
remember that instruments can fail or become inaccurate at any time,
anywhere. Knowing how your
aircraft feels and handles at various speeds and configurations is a
powerful tool to be used in addition to your airspeed indicator.
SkyStar has put together a Static Port Kit P/N 69175.000 that can be purchased through our Customer Service Department, at 208-466-1711. Also, be sure to call us if you have any questions. |
|||||||||||||||||
|
|
|||||||||||||||||
Ultralight
Aircraft News Magazine |
|
||||||||||||||||
|
Ultralight Aircraft News Web Magazine Covering the World of Ultralight Aviation .
You may link to these pages or print
them out for your own personal use, but no part of this
publication may be copied or distributed, transmitted, transcribed,
stored in a retrieval system, or translated into any human or computer
language, in any form or by any means, electronic, mechanical,
manual, or otherwise, without the written permission of Ultralight News.
By copying or paraphrasing the intellectual
property on this site, you're automatically signing a binding contract
and agreeing to be billed $10,000 payable immediately. Copyright Ultralight News . |
|||||||||||||||||
