Van's Aircraft RV-8, Руководство по монтажу

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SECTION 15 FINAL INSPECTION AND FLIGHT TEST RV AIRCRAFT
15-23
SEC 15r8 12/23/10
AIRSPEED INDICATOR MARKINGS
AEROBATICS
Note: The RV-9/9A is NOT designed or intended for aerobatics.
Note: Aerobatic maneuvers as defined by the FAR’s include bank angles greater than 60 degrees relative to
the horizon and nose-up/nose-down pitch angles of 30 degrees relative to the horizon. These maneuvers
must be performed above a minimum altitude of 1500 feet AGL and all participants in the aircraft must wear
a parachute.
RV airframes are stressed for aerobatics up to a gross weight of 1050 lb.for the RV-3, 1375 lb for the RV-4/6/6A, and
1600 lb. for the RV-7/7A and the RV-8/8A with the “Dash One” wing (included in all RV-8/8A kits shipped since Janu-
ary, 2001.) Earlier RV-8/8As with the original wing have an aerobatic gross weight of 1550 lbs.
This means that they have design strengths of 6 positive and 3 negative Gs (plus a 50% safety factor) at up to this
weight. The key word is WEIGHT. RV structures have a certain amount of strength and are capable of carrying a
given load at given G load. If the weight increases, so does the stress. As the empty weight increases, the useful
load decreases —less fuel and pilot/passenger load can be carried within the aerobatic weight limit. For this reason,
a heavy 2-seat RV may become a single place aerobatic airplane because it cannot carry two people and remain
under the aerobatic gross weight limit. We expect that the empty weights of many RV-4s and RV-6/As will be over
1050 lbs. because of optional equipment installed. These will definitely be single place aerobatic airplanes. Some
RVs have been built with such high empty weights that when flown by a pilot weighing much over 200 lb., are no
longer structurally qualified to perform aerobatics at all. Check the specific aerobatic gross weight given in Section
14. Always remember, RVs are
not indestructible. Like all other airplanes, they have been designed with finite limits
which must be observed. As a homebuilt, any individual airplane may have different limits which in all probability will
be lower than design limits.
For or those wishing to do aerobatics in their RVs, aerobatic testing should be done during the later portion of the
flight test period. We suggest that aerobatics be approached cautiously, and only after becoming thoroughly familiar
with control responses, handling qualities, and performance capabilities. The pilot should also have received formal
aerobatic training in other aircraft. Most RVs are capable of easily performing basic aerobatic maneuvers. This ca-
pability is due to their relatively high power loading and to their aerodynamic cleanliness which produces the speed
(energy) needed. But, because of this, excessive speed build-up can occur very quickly, and should be a primary
concern when attempting and practicing aerobatics. As an example, one does not enter a split-s maneuver from
anything near cruising speed (like you see fighters doing in the old movies) because there is no way to complete the
maneuver without exceeding speed and/or G-Load limits. The safe entry speed for a Split-S is around 100-110 IAS.
The point is that RV aerobatics are not the same as Pitts or Citabria aerobatics. Speed builds very fast when pointed
downhill.
Elevator stick forces are relatively light, so it is not a good idea to turn the controls over to a passenger for the pur-
pose of aerobatics. Nor is it a good idea to apply control forces similar to those you may have become accustomed
to in some other aerobatic airplane, say, a Citabria or a Stearman. Over stressing could easily occur. This is why you
should be thoroughly familiar with the flying and handling qualities of your RV before attempting aerobatics. Because
of its light controls, the RV is a pilot-limited airplane. In other words, it is the pilot's responsibility to avoid over stress-
ing the airplane.
Aerobatic Entry Speeds: Refer to the section on maneuvering speed when contemplating aerobatics. Remember
that the maneuvering speed is defined as the highest speed at which full and abrupt controls can be applied without
exceeding the design strength of the airplane. This does not mean that it is the highest permissible aerobatic entry
speed. It just means that for any speed above the maneuvering speed, control inputs must be limited to less than
SPEEDS IN STATUTE MILES PER HOUR RV-4 RV-6/6A
RV-7/7A/8/8A
RV-9/9A
Bottom of White Arc: (Approx. Indicated stall speed with full flaps)
54 55 58 49
Top end of White Arc: (Max. speed with full flaps)
100 100 100 90
Bottom of Green Arc: (Approx. indicated stall speed without flaps)
58 59 64 56
Top end of Green Arc: (Max. structural cruise speed)
180 180 193 180
Blue Line: (Maneuvering speed-Max. permissible speed at which full control can be
applied. Speed at which full elevator control would impose loads exceeding limits
)
134 134 142 118
Yellow arc: (caution range, to be flown only in calm or light turbulence conditions) 180-210 180-210 193-230 180-210
Red Line: VNE IAS (Maximum permissible speed under any condition) 210 210 230 210
SECTION 15 FINAL INSPECTION AND FLIGHT TEST RV AIRCRAFT
15-24
SEC 15r8 12/23/10
full—and less than that needed to produce 6 Gs. Because of the wide speed range (top speed/stall speed) of the
RVs, entry speeds for some maneuvers can also vary over a considerable range. For vertical maneuvers like loops,
Immelman turns, and horizontal eights, the entry speeds have an inverse relationship to the Gs required to complete
the maneuver. An entry speed near the low end of the speed range will require a higher G pull-up than for an entry
speed near the top of the speed range. The entry speeds listed below are presented as general guidelines, as start-
ing points for aerobatic testing. Differing airframe weights, engines, propellers, and pilot preferences will determine
the ideal entry speeds.
x
Loops, Horizontal Eights: 140-190 mph.
x
Immelman Turns: 150-190 mph
x
Aileron Rolls, Barrel rolls: 120-190 mph
x
Snap Rolls: 80-110 mph
x
Vertical Rolls: 180-190 mph
x
Split-S: 100-110 mph
Note: All speeds are statute mph.
Please note that the recommended entry speeds for snap rolls are relatively low. One definition of a snap roll is that it is an acceler-
ated stall with heavy yaw input. Because the RVs have good stall characteristics and good spin resistance, they also resist easy
snap roll entry. Entered at speeds below 100 mph, snaps tend to be slow and wallowing. At above 100 mph, high G loads are
required. For this reason, most RV pilots avoid snap rolls and concentrate on looping and rolling maneuvers more suited to the
performance and handling qualities of these planes.
RECORDING FLIGHT TEST DATA
All pertinent data obtained during flight testing should be recorded in the aircraft log and/or flight manual. This should
include data about limits reached, limit speeds, acceleration (G-loads) limits, etc. This is particularly important if test-
ing limits were lower than suggested in this text. There will be a natural tendency for future pilots of this airplane to
assume that it has been built and tested to the same standard as the prototype and other RVs. If an individual RV
has not been flight tested to the design limits, a clear record of the test limits should be available. An “AEROBATICS
PROHIBITED” placard should be prominently displayed on the instrument panel. Remember, though your RV may
look like all others, it is really a one-of-a-kind airplane because you built it, and it is not identical to any other. Well
recorded data will eliminate the need for assumptions on the part of future pilots. We can do without assumptions in
this business.
A placard stating “This Aircraft is amateur built and does not comply with the federal safety regulations for standard
aircraft” must be visible in the cockpit of your airworthy RV. As the pilot, it is well to reflect on this thought because
you are a passenger also. The federal safety standard were developed for good reason. Just because amateur built
airplanes are not required to comply with all safety regulations and design standards does not exempt them from
suffering the possible consequences of non-compliance. Perhaps it is better for the builder to think of the intended
wording as “has not been shown to comply” rather than “does not comply”. Then, do everything possible to comply
with the highest “self imposed” standards of workmanship and airmanship.
We will close by leaving you with a few quotes borrowed from the FAA Advisory Circular, AMATEUR-BUILT AIR-
CRAFT FLIGHT TESTING HANDBOOK.
“The laws of aerodynamics are unforgiving and the ground is hard.”
Michael Collins.
“The object of the game, gentlemen, is not to cheat death: the object is not to let him play.”
Patrick Poteen, Sgt., U.S.
Army.
“Leave nothing to chance.”
Tony Bingelis
“Know your airplane, know it well, know its limitations, and above all--know your own limitations.” Bob Hoover
“It is critically important that a test pilot never succumb to the temptation to do too much too soon, for that path leads
but to the grave.”
Richard Hallion.
“Always leave yourself a way out.”
Chuck Yeager.
“One can get the proper insight into the practice of flying only by actual flying experiments.”
Otto Lilienthal (1896)
“Keep your brain a couple steps ahead of the airplane.”
Neil Armstrong
“A superior pilot uses superior judgment to avoid those situations which require the use of superior skill.
Old Aviation
Proverb
“Go from the known to the unknown--slowly!”
Chris Wheal, test pilot
.