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Parachute fails to save SR-22



 
 
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  #61  
Old February 5th 05, 09:29 PM
Thomas Borchert
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John,

I
contacted one of their reps about spin recoveries and was told that they
were never tested but could 'possibly' recover normally from a spin


Well, then either you were told wrong or misunderstood. The accepted and
certificated method of spin recovery is pulling the chute.

--
Thomas Borchert (EDDH)

  #62  
Old February 5th 05, 10:13 PM
Bob Moore
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Thomas Borchert wrote

I contacted one of their reps about spin recoveries and was
told that they were never tested but could 'possibly' recover
normally from a spin


Well, then either you were told wrong or misunderstood. The accepted
and certificated method of spin recovery is pulling the chute.


Does having an accepted and certificated method prevent it from POSSIBLY
recovering using a normal spin recovery method? The rep simply stated
that they didn't know since it had never been tested using the normal
spin recovery technique.

Bob Moore
  #63  
Old February 6th 05, 02:25 AM
Kyle Boatright
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"Bob Moore" wrote in message
. 122...
Thomas Borchert wrote

I contacted one of their reps about spin recoveries and was
told that they were never tested but could 'possibly' recover
normally from a spin


Well, then either you were told wrong or misunderstood. The accepted
and certificated method of spin recovery is pulling the chute.


Does having an accepted and certificated method prevent it from POSSIBLY
recovering using a normal spin recovery method? The rep simply stated
that they didn't know since it had never been tested using the normal
spin recovery technique.

Bob Moore


I have a hard time believing that they didn't do spin testing. Perhaps they
just don't want to talk about it. On the other hand, maybe they didn't
spin test, but it seems like one of those things that every manufacturer
would do on each of its models. The result might be "Spins and recovers
nicely" or "Don't spin it.", but if I was laying out a few hundred thousand
dollars, I'd like to have a better answer than "If it happens, you can pull
the red handle, or you can be a test pilot."



  #64  
Old February 6th 05, 03:13 AM
John E. Carty
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"Kyle Boatright" wrote in message
...

"Bob Moore" wrote in message
. 122...
Thomas Borchert wrote

I contacted one of their reps about spin recoveries and was
told that they were never tested but could 'possibly' recover
normally from a spin


Well, then either you were told wrong or misunderstood. The accepted
and certificated method of spin recovery is pulling the chute.


Does having an accepted and certificated method prevent it from POSSIBLY
recovering using a normal spin recovery method? The rep simply stated
that they didn't know since it had never been tested using the normal
spin recovery technique.

Bob Moore


I have a hard time believing that they didn't do spin testing. Perhaps
they just don't want to talk about it. On the other hand, maybe they
didn't spin test, but it seems like one of those things that every
manufacturer would do on each of its models. The result might be "Spins
and recovers nicely" or "Don't spin it.", but if I was laying out a few
hundred thousand dollars, I'd like to have a better answer than "If it
happens, you can pull the red handle, or you can be a test pilot."




They (Cirrus) really don't like to talk about the subject. They'll tell you
that the altitude in which most spins occur prevents most if not all
aircraft from recovering, and instead of asking why they have to have a CAPS
system to be certified (due to lack of spin recovery) that you should be
asking why more aircraft manufactures aren't incorporating the system to
save lives :-)


  #65  
Old February 6th 05, 03:18 AM
John W. Galvin
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"Larry Dighera" wrote in message
...
On Fri, 4 Feb 2005 19:14:09 -0600, "John W. Galvin"
wrote in
::

The Cirrus is supposedly recoverable in a spin, with one change
from the usual procedu the yoke is supposed to be
moved briskly forward to the stop.


That's interesting. First I've heard of it. What is the source of
that information?

I presume that spin recovery method is not mentioned in the POH. I
can imagine situations where it might be preferable to 'chute
deployment if it was truly a certifiable spin recovery option.


Your e-mail address looked valid. I don't want to know how much spam you
must receive. I sent you a copy of the JAA PDF. It documents the method
mentioned.

The POH for the SR22 had spin recovery documented, but that text was removed
in later revisions in favor of the CAPS as only method of spin recovery. My
guess would be that the lawyers made that decision.

--Galvin


  #66  
Old February 6th 05, 03:47 AM
Morgans
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Default


"Kyle Boatright" wrote

The result might be "Spins and recovers
nicely" or "Don't spin it.", but if I was laying out a few hundred

thousand
dollars, I'd like to have a better answer than "If it happens, you can

pull
the red handle, or you can be a test pilot."



Most fatal spins are low altitude, takeoff and landing stall /spins. There
is not enough altitude to recover with spin recoveries, or the chute, so
what does it really matter, anyway?
--
Jim in NC


  #67  
Old February 6th 05, 04:39 AM
vincent p. norris
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The Cirrus is supposedly recoverable in a spin, with one change from
the usual procedu the yoke is supposed to be moved briskly forward to the stop.


That's exactly how I was taught to recover from a spin, both in J-3s,
T-crafts, Airknockers, etc, and by the Navy. (Along with opposite
rudder, of course.) Why is it a "change from the usual..."?

vince norris
  #68  
Old February 6th 05, 02:59 PM
Neil Gould
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Recently, Morgans posted:

"Kyle Boatright" wrote

The result might be "Spins and recovers
nicely" or "Don't spin it.", but if I was laying out a few hundred
thousand dollars, I'd like to have a better answer than "If it
happens, you can pull the red handle, or you can be a test pilot."



Most fatal spins are low altitude, takeoff and landing stall /spins.
There is not enough altitude to recover with spin recoveries, or the
chute, so what does it really matter, anyway?

It matters some because "most" spins are not "all" spins. It is important
to know how to recover from a spin, and in that regard, Cirrus has
indicated how that is done in their aircraft; pull the 'chute. I fail to
see why it is a point of debate for those of us who aren't a part of their
testing program.

Neil



  #69  
Old February 6th 05, 06:48 PM
Larry Dighera
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Default

On Sat, 5 Feb 2005 20:18:10 -0600, "John W. Galvin"
wrote in
::

"Larry Dighera" wrote in message
.. .
On Fri, 4 Feb 2005 19:14:09 -0600, "John W. Galvin"
wrote in
::

The Cirrus is supposedly recoverable in a spin, with one change
from the usual procedu the yoke is supposed to be
moved briskly forward to the stop.


That's interesting. First I've heard of it. What is the source of
that information?

I presume that spin recovery method is not mentioned in the POH. I
can imagine situations where it might be preferable to 'chute
deployment if it was truly a certifiable spin recovery option.


I sent you a copy of the JAA PDF.


Thank you.

Are you able to provide a link to the web address for that document?

I'll include a text copy of the (manually formatted) 21 page .PDF file
here with comment below:

------------------------------------------------------------
CRI B-2 Page 1 of 21

CIRRUS DESIGN SR 20
Regulation ref. : JAR 23.221
Advisory Material/Policy Ref. :
Subject : Equivalent of safety for Spin requirement
CRI n° : B-2
Issue n° : issue 6
Date : March 2004
CRI Status : open
Next action by : EASA
CRI Closure target :
April 2004

STATEMENT OF ISSUE
The SR20 was designed to inhibit departure from controlled flight. The
FAA has found that this enhances stall performance, and together with
an airframe parachute, provides safety at least equal to spin
requirement of FAR 23.221. The applicant is requesting an identical
equivalent safety finding from the JAA. The paragraphs FAR and JAR
23.221 are in the SRD list (FAR 23.221 includes the spin resistance
concept, the JAR 23.221 does not).

DISCUSSION

JAA Position:
As the regulatory basis is different, the Applicant must show that the
aeroplane complies with the paragraph JAR 23.221 or demonstrate that
its concept provides an equivalent level of safety to the JAR 23.221.
1- It is asked to Cirrus Design and the FAA to provide additional
information on the aeroplane stall characteristics and spin behaviour.
2- It is asked to Cirrus Design and the FAA to propose a clear
emergency procedure for the spin departure in the AFM.
The JAA validation team will study the material provided for points 1
& 2. After this review, the granting of an exemption to paragraph JAR
23.221 will be considered taking into account :
• the FAA Equivalent Level Of Safety
• the spin recovery qualities of the SR 20 aeroplane (number of
necessary turns and loss of height)
• the position of the JAR 23 Study Group on the concept
The revision of this CRI B-2 will be sent to the NFPs for comments.

CRI B-2 Page 2 of 21

CIRRUS DESIGN position:
Basis for Equivalent Level of Safety
Enhanced stall characteristics, providing increased resistance to
departure from controlled flight, and the Cirrus Airframe Parachute
System provide an equivalent level of safety to FAR/JAR 23.221, Spins.

1. Safety Analysis
Cirrus designed the SR20 aircraft between 1994 and 1998. Cirrus
initiated the design program with safety as a primary objective.
Cirrus was aware of wing design features that could offer significant
improvement to lowspeed flight characteristics and stall behavior, and
therefore increased safety levels. These features included leading
edge extensions at the outboard wing sections set at chord incidence
angles less than that at the inboard wing sections. Research conducted
by NASA LaRC (ref. AIAA Paper 86-9812) indicated that during lowspeed
flight the modified aircraft retained improved roll control and
increased resistance to stall departure in normal and uncoordinated
control configurations. The research also indicated that the design
features could contribute to an inverse effect on spin recovery once
the aircraft has departed. Cirrus and the FAA conducted an extensive
review of safety statistics. The results of this review can be
located in the FAA Equivalent Level of Safety finding ACE-96-5,
Appendix 1. The research concluded that “only about 0.5% of the total
airplanes, or just short of 1% of those prohibited from spinning, were
in an environment that would have allowed a recovery.” This result is
primarily due to many departures from controlled flight being at
altitudes too low to recover through the use of control movement. The
FAA research showed that “Stall/Inadvertent” was the second largest
cause of US Fixed Gear Fatal Accidents (at about 17%), and that when
added to the categories of “Stall/Reckless low altitude” (5%), and
“controllability”(2%), these types of stall departure accidents
together cause more fatal accidents than the largest single cause
category.
The FAA concluded that in order to break this longstanding statistical
pattern of the largest percentage of fixed gear fatal accidents
resulting from a lack of controllability in the stall, they would have
to think “out of the box” with new technology or compliance
approaches. The FAA was willing to do so because the safety
benefit potential is great. (ref. FAA Presentation to JAA General
Aviation Sub-Certification Sectorial Team, 26 February 2003). Based on
this research and conclusions, the FAA supported Cirrus’ alternative
wing design approach with the understanding that overall safety levels
would be improved through the prevention of departures, by way of
improved low-speed characteristics and departure resistance, than by
meeting the combined requirements of 23.201 and 23.221.

2. Equivalent Level of Safety
The safety analysis concluded that departure resistance could
contribute significantly more to improved levels of safety than
departure recovery. The FAA defined a significant increase in
low-speed control and departure resistance requirements in the ELOS.
These requirements deliver increased levels of safety applicable to
both low and high altitude maneuvering. The requirements as stated in
the ELOS are as follows:
a. During the stall manoeuvres contained in § 23.201, if an
uncontrollable downward pitching does not occur, the pitch control
must be held against the stop and controllability must be
demonstrated. Using coordinated rudder and aileron control inputs, it
must be possible to maintain wings level flight within 15 degrees of
bank of level flight without using exceptional skill or alertness.
Additionally, it must be possible to roll the airplane from 15 degrees
of bank in one direction to 15 degrees of bank in the opposite
direction in the stick full aft condition without the use of
exceptional skill or alertness.
b. If an uncontrollable downward pitching does occur, it must be
possible to hold the stick full aft for at least two seconds after the
nose pitches downward while maintaining wings level within 15 degrees
of bank. At the end of two seconds, standard stall recovery control
inputs must produce an immediate return to unstalled flight without
any undue tendencies towards spin entry.
c. The stall characteristics must not be unduly sensitive to sideslip
during abused stall entries. There must be no uncontrollable tendency
to spin with small deviations from coordinated flight during the
stall and the recovery. The use of aileron and rudder controls must
not require a high degree of skill or CRI B-2

Page 3 of 21

alertness. The ailerons must produce correct, unreversed and effective
response throughout the stall and recovery.
d. Following an abused control entry stall controllability
demonstration, the aircraft must respond immediately and normally
without unreversed use of the controls and without exceeding the
temporary control forces specified in § 23.143(c) to regain
coordinated unstalled flight. The FAA also determined, as stated in
the ELOS, that the probability of high altitude loss of control is
very low. In the event that control is lost, the CAPS system provides
an effective means to protect the occupants.
The departure resistance aspects of the ELOS are primary, but the
presence of the CAPS system is an additional risk mitigating feature
due to its ability to recover the aircraft in less than 1000 feet.
In its presentation to the JAA Sectorial Team on February 26, 2003,
the FAA re-stated its philosophy. The primary focus is to prevent
departure from controlled flight / spin entry, through three aspects.
• First, the FAA found that the enhanced stall handling
characteristics are based on the intent of the spin
resistance requirements.
• Second, the FAA found that the improved departure resistance
addresses the real issue driving the
accident rate – inadvertent departure from controlled flight – and
that this supports the US Department
Of Transportation’s safety mandate.
• Third, the FAA concluded that the Cirrus wing treatment and handling
characteristics are parallel to NASA research.

The FAA’s secondary focus of addressing these accidents is the low
altitude departure recovery being possible using the CAPS system, The
FAA noted that the CAPS system recovers the airplane in the same or
less altitude than airplanes in the same class take to recover from
the one-turn spin requirement of sec. 23.221. The FAA saw the stall
handling characteristics providing the ability to recover from a stall
without losing control or entering a spin, and the CAPS system as a
second line of defense. (John Colomy, FAA, address to the
Sectorial Team on 26 February 2003)
JAA Requested Items
1. Provide additional information on SR20 Stall characteristics and
Spin behavior. Cirrus engaged in an extensive flight test program to
investigate the stall characteristics and spin behavior of
the Cirrus SR 20, with over 60 spin entries, and the stall and
departure preceding the spin entries.
a. Stall Behavior
i. Requirements. See above ELOS text for requirements. After this
flight test program, Cirrus continues to believe that the standards
set in the ELOS are correct. The stall departure standards set for the
SR20 simulate realistic inadvertent stall situations.
ii. Results. The SR20 meets or exceeds the ELOS requirements in all
required configurations. See SR20 TIR for detail on stall results in
Appendix 2. The Airplane retains roll control throughout the stall.
The airplane can be rolled from 15 degrees of bank in one direction to
15 degrees of bank in the other direction with the stick full back
with typical pilot skill. iii. Comments. FAA and JAA test pilots have
formally and informally flown the SR20 and agree that the aircraft
meets or exceeds the ELOS requirements, is tolerant of slow speed
uncoordinated control movements, and provides the pilot with
significant time and indications to apply corrections.

CRI B-2 Page 4 of 21

b. Spin Behavior
i. Test Matrix. A limited investigation of the SR20 spin behavior
has been completed and results are contained in Cirrus Design reports
12419, title, and 15568, title. The incipient spin and recovery
characteristics were examined during more than 60 total spin entries
covering the following configurations.

Configuration 1
Normal Spins Level Entry C.G.

Clean-Power Off 1 Left & 1 Right Fwd2, Mid, Aft
Takeoff-Power Off 1 Left & 1 Right Fwd
Landing-Power Off 1 Left & 1 Right Fwd
Clean-Power On 1 Left & 1 Right Fwd 2

1. All spins conducted at gross weight.
2. Also evaluated accelerated entries, 30 degree banked turn
entries, and effects of ailerons against the spin direction.
ii. Results. The aircraft recovered within one turn in all cases
examined. Recovery controls were to reduce power, neutralize ailerons,
apply full rudder opposite to spin, and to apply immediate full
forward (nose down) pitch control. Altitude loss from spin entry to
recovery ranged from 1,200 – 1,800 feet. Detail results can be found
in the above referenced reports.
iii. Comments. No spin matrix less than that prescribed in AC23-8A
or AC23-15, can determine that all configurations are recoverable. It
must be assumed that the SR20 has some unrecoverable characteristics.
In the SR20 proper execution of recovery control movements is
necessary to affect recovery, and aircraft may become unrecoverable
with incorrect control inputs. These spins enabled Cirrus to gain
additional understanding of both the stall departure characteristics
of the airplane and the necessary spin recovery techniques.

2. Propose a clear emergency AFM Procedure for CAPS use.
a. Current Procedure. The current procedure is in AFM section 3 –
Inadvertent Spiral/Spin Entry, for detail see Appendix 3. The
procedure for inadvertent spin entry notes that the CAPS system is
the only approved and demonstrated method for spin recovery. The
current procedure also provides guidance to determine if the aircraft
is in a recoverable spiral/incipient spin or is unrecoverable and,
therefore, has departed controlled flight if time and altitude permit.
The guidance includes a description of potential recovery controls.
The procedure requires CAPS activation if the aircraft cannot be
recovered.
b. Discussion. Based on the spin testing conducted to date, the
Cirrus SR20 has exhibited the requirement for unique and specific
recovery controls. A majority of the general aviation pilot population
do not receive any spin recovery training whatsoever, and no
type-specific training in the SR20 is made available. Some non-US
general aviation private pilots receive limited spin recovery basic
and recurrency training, and no type-specific training is available.
The Cirrus test pilot performing the spin program noted that while all
spins entered were recoverable, they required a method of spin
recovery that, while not unique in light general aviation airplanes,
is different from that of a light trainer airplane in which a pilot is
likely to receive spin training. Significant variability in spin
recovery training techniques also exists – ranging from merely
releasing the elevator control in some light trainers, to movement of
the control to neutral, to brisk forward movement to neutral, to brisk
foreward movement past neutral, etc.. In the case of the SR20, the
proper spin recovery procedure is to briskly move the elevator control
to the full down position. This is an unnatural control movement, when
the nose of the aircraft may already appear to the pilot to be
pointing down sharply. This is also a movement not typically advocated
by spin training instructors due to associated discomfort.

CRI B-2 Page 5 of 21

The reliability level of a general aviation pilot to properly react in
a loss of control condition in any type of airplane is historically
low (see the FAA statistics). Cirrus has determined that the
probability of the typical general aviation pilot properly applying
the SR20 recovery controls to assess if the aircraft has permanently
departed controlled flight is likewise low. While a small percentage
of Cirrus pilots may be able to successfully recover from an
inadvertent spin, Cirrus contends that the far larger portion of
pilots would not do so in a surprise departure spin situation.
Cirrus has accordingly concluded, as a result of the further extensive
flight test conducted pursuant to the JAA Study Group direction in
April 2000, that in an inadvertent spin entry, time and altitude
is too critical to allow for any pilot reaction except the simple and
quick process of reaching for the CAPS handle and activating the
system. Cirrus believes it is better to accept some airframe
losses through CAPS activation when the airplane could have been flown
away following a successful recovery, in order to save the lives of
the far larger number of pilots who would not be able to successfully
execute a spin recovery.
c. Proposed Procedure. Cirrus has reached strong conclusion that any
spin recovery guidance in the AFM distracts pilot from immediately
activating CAPS system when the aircraft has departed controlled
flight. Cirrus is removing existing references to spin recovery in its
current AFM. The clear AFM procedure will be to activate CAPS system
in the event that control is lost. The new proposed procedure can be
found in Appendix 4.

Position Summary
1. Cirrus and the FAA reviewed accident statistics and concluded that
spin recovery characteristics have minor affect on safety levels,
while stall/departure characteristics have significant impact.
2. Cirrus achieved excellent low-speed control and departure
resistance through wing design features. Cirrus supplemented this
safety level with a standard CAPS system.
3. Cirrus proceeded with spin investigation per JAA direction.
4. Cirrus found that recovery techniques are Cirrus SR20 specific,
pilot spin recovery proficiency is generally poor, and critical
altitude is wasted in recovery attempt.
5. Cirrus concludes that any pilot reaction other than immediate
activation of the CAPS system is promoting a lesser safety level.
6. Cirrus is making AFM changes to clarify loss of control response
and CAPS deployment procedure.
7. Any AFM/Training directions regarding spin recovery would promote a
lesser safety level than CAPS usage. Inclusion of guidance may save
some airframes, but increases risk to many.
8. Cirrus requests the JAA to accept this response to the Study Group
and compliance to FAA ELOS, with new AFM language, as the basis for
compliance to a JAA exemption or Equivalent Level of Safety to 23.221.

CRI B-2 Page 6 of 21

FAA position :
The FAA agrees with the Cirrus position and continues to promote the
spin resistance concept as more effective in preventing stall/spin
accidents. The FAA stands behind its original Equivalent Level of
Safety for section 23.221 and commends Cirrus for stepping up to the
additional research, development, flight test, and certification work
when compared to a traditional spin program. It is our hope that other
manufacturers will see the safety merits of this approach to
preventing stall/spin accidents and follow Cirrus's lead so that the
FAA can begin to see a reduction in this significant cause of fatal
accidents.
During the SR20 certification, the FAA participated in the ELOS stall
tests certification. The low speed maneuvering handling qualities are
excellent as are the stall and post stall handling qualities. Each
production aircraft is evaluated during the production flight tests to
verify that it meets the ELOS requirements.

JAA Position:
1- The issue of the additional information on the aeroplane stall
characteristics and spin behaviour will be discussed during the
November 2003 meeting.
[2- missing from .PDF document]
3- The new emergency procedure for the spin departure in the AFM is
clear and accepted by the JAA team.

JAA Position (December 2003):
The JAA team has drafted a special condition which is in Annex. As the
FAA and the Applicant expressed a strong concern with this position,
and in respect to the JAA procedure, an JAA adhoc group will discuss
this matter.

JAA Position (February 2004):
The JAA adhoc group has discussed the draft SC. In conformity with the
EASA procedures, this SC will be submitted to comments.

CONCLUSION
The CRI is open.

CRI B-2 Page 7 of 21

U.S. Department of Transportation Federal Aviation Administration
Subject: ACTION: Equivalent Level of Safety to § 23.221;
Cirrus Designs SR-20; Finding No. ACE-96-5
Date:
From: Manager, Chicago Aircraft Certification Office,
ACE-115C
Reply to
Attn. of:
L. Foster
ACE-111
(816) 426-5688
To: Manager, Small Airplane Directorate, ACE-100

This memorandum requests your office to review and provide concurrence
with the proposed finding of equivalent level of safety to the spin
requirements of § 23.221 of 14 CFR Part 23.

BACKGROUND:
The Cirrus SR-20 is a 2,900 pound single-engine, four-place,
fixed-gear airplane powered by a 200 hp reciprocating engine. It has a
conventional tractor configuration and utilizes composites for the
structure. Some unique features of the SR-20 include sidestick
controls and a ballistic recovery system based on the General Aviation
Recovery Device (GARD) 150 certificated for the Cessna 150/152 series
airplane. Cirrus plans to offer the GARD system as standard equipment,
meeting special conditions specifically for a TC’d installation. The
special conditions for the GARD prior to the SR-20 were for a
supplemental safety device and not a primary safety device. Cirrus is
incorporating the GARD as a primary safety device and requests the FAA
to give them credit for the system by accepting it as a safety
device equivalent to § 23.221 Spins.

APPLICABLE REGULATIONS:
Section 23.221 requires that single-engine, normal category airplanes
must demonstrate compliance with either the one-turn spin or the
spin-resistant requirements. The airplane, for spin compliance, must
recover from a one-turn spin or a three-second spin, whichever takes
longer, in not more than one additional turn after the controls have
been applied for recovery. This should be demonstrated for all
configurations.
Appendix 1
Memorandum

CRI B-2 Page 8 of 21

APPLICANT POSITION:
The Cirrus SR20 will include a GARD, emergency aircraft recovery
parachute system, as a part of its type design. This system provides
an Equivalent Level of Safety to 14 CFR Part 23, § 23.221 Spinning.
1. Level of Safety Baseline: Section 23.221 provides for a level of
safety to the occupants. This establishes a baseline to which other
means of achieving this level of safety may be compared. The level
of safety attained provides for a "margin of safety" when recovery
from a stall is delayed by one turn or three seconds, whichever is
longer. The "margin of safety" must be a recovered aircraft within one
additional turn. Significant amounts of data exist, which creates the
foundation for the baseline, to substantiate the typical altitude loss
for similar class aircraft.
2. Alternate Equivalent Level of Safety: The inclusion of the
parachute recovery system in the original type design provides for an
appropriate "safety margin," or equivalent level of safety. In order
for the system to deliver this level of safety, the altitude loss for
recognition and deployment of the emergency chute must be shown to be
less than or equal to the typical altitude loss for a spin. A
three-second delay is recommended to simulate the recognition period
of this event.
3. Compliance:
Baseline Established
a) Compile historical spin data.
b) Examine spin data for similar class aircraft.
c) Determine typical altitude loss for two turn spins, "A" feet.
Parachute System Level of Safety Established
a) Apply control input during stall to initiate spin.
b) Allow three-second delay from initiation.
c) Complete GARD system activation procedures.
d) Allow for full chute inflation.
e) Measure total altitude loss from initial stall, "B" feet.

Compliance Disposition
If "A" is greater than or equal to "B," the GARD system provides an
equivalent level of safety to that of the baseline.
The basic plan outlined above provides a rational means for
establishing the equivalent level of safety.

CRI B-2 Page 9 of 21

FAA POSITION:
The current rule requires that normal category, single-engine
airplanes must recover from a one-turn spin in less than one
additional turn with no limit to altitude loss. To show equivalent
safety, an applicant must show that the action taken provides a level
of safety equal to that established by the regulation from
which relief is sought. There has been confusion in the past as to
what constitutes "equivalent" safety.
The confusion is between using the literal "letter" of the rule and
the "spirit" of the rule. Not all rules have one-to-one equivalents.
Behind each rule there is an intent, the protection envisioned as a
result of the rule. Equivalent safety findings must show equivalency,
either by a one-to-one equivalent or by meeting that original safety
intent of the rule. The spin recovery requirements of § 23.221 were
intended to ensure that the pilot had a chance to safely recover the
airplane after inadvertently departing controlled flight into a flight
regime that is often fatal. These recovery requirements are only
effective if the pilot applies the correct anti-spin controls and
there is enough altitude to recover.
The GARD system must meet the special conditions associated with this
type certificate. The special conditions include requirements to show
that serious injury to the occupants is unlikely, including
operation during adverse weather conditions. The landing protection
provided by the GARD system meeting these special conditions is
assumed to generally allow the occupants to walk away, provided the
system was activated above the minimum deployment altitude. All
discussion concerning the GARD system is based on the special
conditions being met.

DISCUSSION:
From 1945 to 1962, all normal category airplanes under 4,000 pounds
had to meet the one-turn spin test. Prior to 1945, the requirement was
a six-turn spin with recovery in no more than one and one-half
additional turns with controls neutral and power off. Amendment 3-7 of
CAR 3, in 1962, eliminated the 4,000 pound limit for single-engine
airplanes and deleted the spin requirement for multiengine airplanes.
The rationale for deleting the spin requirements for twin-engine
airplanes was that spin prevention will contribute more toward
reducing stall-spin accidents than spin recovery; therefore, the
engine-inoperative stall requirements were revised to preclude
inadvertent spin tests. No reason was provided for requiring
all single-engine airplanes, regardless of weight, to meet the spin
requirement.
The requirement to demonstrate spin recovery for the private pilot’s
license was eliminated in 19491. Since then, the stall/spin accident
rate has only improved. However, the overall fatal accident rate in
general aviation is basically unchanged over the past 15 years. The
1994 Nall Report on accident trends and factors indicates that over 40
percent of the serious accidents in fixed-gear, single-engine
airplanes today begin in maneuvering flight. A stall/spin accident is
almost always the end result, except that most airplanes never get to
the spin phase before impacting the ground, indicating that this is
really a stall problem. These findings suggest that the FAA should
consider new approaches to enhance the stall handling characteristics.
Half (864 out of 1771) of the fatal accidents studied by the
directorate involving spins are in airplanes certificated in the
utility or acrobatic categories and approved for multiple turn
spins, unlike normal category airplanes, which are prohibited from
intentional spins. Using FAA accident data that went back to 1972,
1,771 "stall/spin" accidents were reviewed. The singleengine
airplanes that were studied had to, as a minimum, demonstrate recovery
from one-turn spins. By reading each of the remarks sections of the
accident report and correlating that with the "phase of flight"
field, it was possible to evaluate whether or not the airplane was
above or below pattern altitude. An inadvertent departure below
pattern altitude is considered unrecoverable; one above pattern
altitude, 1 Private pilot’s license only requires that the pilot know
the spin recovery procedure. No requirement to even do a spin. With
the exception of flight instructor, all subsequent pilot ratings don’t
even require full stalls, only recovery from incipient stalls.

CRI B-2 Page 10 of 21

especially at a safe training altitude, was considered to be
recoverable. Out of the 1,771 accidents, only
7% (130) were above pattern altitude. Almost half of those 7% were in
airplanes that had undergone extensive spin testing for certification.
These 3.3% were approved for multiple turn spins. The remaining
3.7% of the airplanes that crashed were only tested for recovery from
one turn spins and were certificated as prohibited from intentional
spins. Further evaluation revealed that, out of the 3.7% of the
airplanes prohibited from spinning, 87% of the those involved weather.
So, only about 0.5% of the total airplanes, or just short of 1% of
those prohibited from spinning ( 9 airplanes in this study), were in
an environment that would have allowed a recovery.
The FAA believes that the GARD system will increase the safety for the
low altitude departure cases. The FAA did consider the case that in an
inadvertent stall/spin at altitude, pilots may try to recover the
airplane and crash before they use the GARD system due to a fear of
damaging the airplane. The FAA acknowledges that an unknown percentage
of pilots will probably try to recover the airplane and will
crash. This is the same scenario as the military experiences with
ejection seats. The majority of crews use the ejection seats and
survive, but a minority of crews stay with the airplane, passing up
the opportunity to safely eject.
The number of inadvertent departures that occur annually are unknown.
The FAA could speculate that it is a low number because if the number
of inadvertent departures were large, the FAA would be aware of
them. One possible explanation that this reported rate is low is
because aircraft are required to meet a spin recovery standard. The
FAA also sees merit in exploring the post stall flight regime;
however, based on a typical flight profile, the opportunity for stall
above pattern altitude is very low except for training.
Therefore, the FAA believes this high altitude risk of departure is
low considering the possible benefits of addressing the low altitude
environment, where the risk of stall is much higher.
Our current stall handling characteristic tests were intended to
provide a margin of safety from inadvertent stall that results in
departing controlled flight. It is clear when reviewing the safety
record that the requirement for compliance means does not necessarily
assure this margin. The FAA, therefore, is concerned that an applicant
installing the GARD system would not conduct any spin or spin entry
evaluation and could have little margin of safety from inadvertent
departure (using current stall handling characteristic requirements).
The result leaves the pilot with little margin from a departure and
forces the use of the GARD system. There is unanimous agreement within
the FAA that the GARD system was never intended as a routine solution
to inadvertent spins. It was intended as device of "last resort"
should the airplane ever depart controlled flight. Serious damage to
the airplane in an off-field landing is not the same as returning to
home base with an undamaged airplane.
The exposure to the hazard of an inadvertent stall/spin at a cruising
altitude is very low. Conversely, every flight requires a takeoff and
landing. Exposure to the hazard of low altitude inadvertent stall is
high. Stall/spin accidents occur at pattern altitude or lower because
that is where the airplane is flying at speeds near stall. In all
scenarios (see chart - attachment) at low altitude, the GARD system
has the potential to provide an equal or greater level of safety than
that offered by the spin recovery requirements.
In most cases, the airplane will impact the ground before completing
one revolution, so spin recovery is not even an issue. Installation of
the GARD system creates incentives and encourages new approaches to
compliance that may improve the safety over that offered by the
existing light airplane fleet.
Based on the foregoing, the FAA will grant relief from the spin
requirements of § 23.221. In doing so, the FAA must also consider all
possible applications of any position taken, so that policy positions
are consistently applied and available to all manufacturers. Even
though the FAA believes that the GARD system should increase the level
of protection offered for inadvertent stalls at low altitude, the FAA
has a responsibility to be conservative concerning the high altitude
departures. Therefore, to show equivalent safety from spin recovery,
in addition to the GARD recovery system, the FAA believes that the
margin of

CRI B-2 Page 11 of 21

protection from spin entry provided by the stall handling
characteristics requirements must be increased.
The current stall requirements, §§ 23.201 and 23.203, are demonstrated
in a coordinated stall.
The intention for increasing the margin of protection is to provide a
reasonable level of confidence that an unintentional, uncoordinated
stall will not result in a spin entry. The FAA’s intent is to increase
the margin of safety around the stall. This approach should not be
confused with the "spin resistance" provision in § 23.221, which
requires the airplane to fly through "extreme" cross-controlled
maneuvers.
Though the stall handling concepts are the same, the spin resistance
requirements are very conservative, show equivalency to spins.

COMPENSATING FEATURES:
The FAA finds that the GARD system offers the same level of safety as
provided for in § 23.221 spins, provided the following conditions are
met.
1. The GARD system must recover the airplane in the same or less
altitude than airplanes that are in the same class typically take to
recover from the one-turn spin requirement of § 23.221.
2. The GARD system must not be deployed before one turn or three
seconds, whichever takes longer, after spin initiation.
3. The Cirrus Model SR-20 must demonstrate enhanced stall
characteristics that parallel the following guidelines:
a. During the stall maneuvers contained in § 23.201, if an
uncontrollable downward pitching does not occur, the pitch control
must be held against the stop and controllability must be
demonstrated. Using coordinated rudder and aileron control
inputs, it must be possible to maintain wings level flight within 15
degrees of bank of level flight without using exceptional skill or
alertness. Additionally, it must be possible to roll the airplane from
15 degrees of bank in one direction to 15 degrees of bank in the
opposite direction in the stick full aft condition without the use of
exceptional skill or alertness.
b. If an uncontrollable downward pitching does occur, it must be
possible to hold the stick full aft for at least two seconds after the
nose pitches downward while maintaining wings level within 15 degrees
of bank. At the end of two seconds, standard stall recovery control
inputs must produce an immediate return to unstalled flight without
any undue tendencies towards spin entry.
c. The stall characteristics must not be unduly sensitive to sideslip
during abused stall entries. There must be no uncontrollable tendency
to spin with small deviations from coordinated flight during the stall
and the recovery. The use of aileron and rudder controls must not
require a high degree of skill or alertness. The ailerons must produce
correct, unreversed and effective response throughout the stall and
recovery.
d. Following an abused control entry stall controllability
demonstration, the aircraft must respond immediately and normally
without unreversed use of the controls and without exceeding the
temporary control forces specified in § 23.143(c) to regain
coordinated unstalled flight.

CRI B-2 Page 12 of 21

4. An additional limitation must be added to § 23.1583 to require GARD
deployment if the airplane departs controlled flight.

CRI B-2 Page 13 of 21

5. The GARD must meet the special conditions prescribed for the Cirrus
Model SR-20 airplane.
Concurred by:
Manager, Chicago Aircraft Certification Office, ACE-115C Date
Manager, Standards Office, ACE-110 Date
Manager, Small Airplane Directorate, Date
Aircraft Certification Service, ACE-100

CRI B-2 Page 1/2

Attachment 1

Figure 1.
Inadvertent Case Current Spin Req. GARD Equipped
Training (at altitude) recovers recovers
Takeoff - gust,stall won’t recover won’t recover
Takeoff - crosswind
turn won’t recover may recover
Takeoff - excessive
nose-up trim - stall won’t recover won’t recover
turning downwind to
base may recover recovers
turning base to final won’t recover may recover
landing - gust, stall won’t recover won’t recover
maneuvering - high recovers recovers
maneuvering - low won’t recover may recover
IFR - disoriented -
departs won’t recover recovers
Go around - excessive
nose-up trim - stall won’t recover may recover

Note: A recovery for the GARD system refers to occupant protection
only. The airplane will be damaged or destroyed anytime the GARD
system is used.

filename: T:\112\lowell\regulat\SR20EL-2
edited3/31/97:K:\ace111\pnining\elos\cirr.doc
edited6/20/97:K/ace111/pninge/elos/cirr.doc
cirr3.doc:10/2/97:X5688:K:\ace111\pnininge\elos\cirr3.doc
Cirrus ELOS Final.doc 10/8/99:

CRI B-2 Page 2/2
Appendix 2 – SR20 TIR Stall Data

CRI B-2 Page 1/2
Appendix 3 – SR20 AFM Section 3
Inadvertent Spin Entry
The SR22 is not approved for spins, and has not been tested or
certified for spin recovery characteristics. The only approved and
demonstrated method of spin recovery is activation of the Cirrus
Airframe Parachute System (See CAPS Deployment, this section). Because
of this, if the aircraft “departs controlled flight,” the CAPS must be
deployed.
While the stall characteristics of the SR22 make accidental entry into
a spin extremely unlikely, it is possible. Spin entry can be avoided
by using good airmanship: coordinated use of controls in turns, proper
airspeed control following the recommendations of this Handbook, and
never abusing the flight controls with accelerated inputs when close
to the stall (see Stalls, Section 4).
If, at the stall, the controls are misapplied and abused accelerated
inputs are made to the elevator, rudder and/or ailerons, an abrupt
wing drop may be felt and a spiral or spin may be entered. In some
cases it may be difficult to determine if the aircraft has entered a
spiral or the beginning of a spin.
If time and altitude permit, the following procedures may be used to
determine whether the aircraft is in a recoverable spiral/incipient
spin or is unrecoverable and, therefore, has departed controlled
flight.

... WARNING ..
... In all cases, if the aircraft enters an unusual attitude from which
recovery is not expected before ground impact, immediate deployment of
the CAPS is required.
... The minimum certified altitude loss for a CAPS deployment from a
one-turn spin is 920 feet. Activation at higher altitudes provides
enhanced safety margins for parachute recoveries. Do not waste time
and altitude trying to recover from a spiral/spin before activating
CAPS.
1. Power Lever.......................................IDLE
2.Control Yoke.......................................Neutral
3. Rudder ...................Briskly Apply Opposite Yaw/Spin Direction
... Note ..
If disorientation precludes visual determination of the direction of
rotation, refer to the symbolic airplane in the turn coordinator. If
the spiral/spin was entered while applying rudder, then the opposite
rudder should be applied for recovery.
4. Just after the rudder reaches the stop, move the yoke briskly
forward far enough to break the stall. Full down elevator may be
required. Hold these control inputs until rotation stops. Premature
relaxation of control inputs may prolong the recovery.
5. After rotation stops, neutralize rudder, and make a smooth recovery
from the resulting dive. Add power as required. Be prepared for
possible engine power loss if rotation causes fuel starvation.
If the above steps do not recover the aircraft and/or it has been
determined that the aircraft has departed controlled flight:
6. CAPS.............................................. .Activate

CRI B-2 Page 2/2
Appendix 4 – SR20 AFM Section 3 (Proposed)
Inadvertent Spin Entry
The SR22 is not approved for spins, and has not been tested or
certified for spin recovery characteristics. The only approved and
demonstrated method of spin recovery is activation of the Cirrus
Airframe Parachute System (See CAPS Deployment, this section). Because
of this, if the aircraft “departs controlled flight,” the CAPS must be
deployed.
While the stall characteristics of the SR22 make accidental entry into
a spin extremely unlikely, it is possible. Spin entry can be avoided
by using good airmanship: coordinated use of controls in turns, proper
airspeed control following the recommendations of this Handbook, and
never abusing the flight controls with accelerated inputs when close
to the stall (see Stalls, Section 4).
If, at the stall, the controls are misapplied and abused accelerated
inputs are made to the elevator, rudder and/or ailerons, an abrupt
wing drop may be felt and a spiral or spin may be entered. In some
cases it may be difficult to determine if the aircraft has entered a
spiral or the beginning of a spin.
... WARNING ..
... In all cases, if the aircraft enters an unusual attitude from which
recovery is not expected before ground impact, immediate deployment of
the CAPS is required.
... The minimum certified altitude loss for a CAPS deployment from a
one-turn spin is 920 feet. Activation at higher altitudes provides
enhanced safety margins for parachute recoveries. Do not waste time
and altitude trying to recover from a spiral/spin before activating
CAPS.
1. CAPS.......................................... Activate per
procedures in AFM section 3 – CAPS Deployment

CRI B-2 Page 3/2
Appendix 5 – JAA proposed special condition
JAA Draft special condition for the Cirrus SR 20 Validation of the FAA
Certification
Edition 3, 29 January 2004

1- Spinning
The aeroplane must comply with the intent of the JAR 23.221. An
equivalent level of safety to JAR 23.221 must be shown by
a combination of enhanced stall characteristics, additional design
features and appropriate demonstration of spins. The aircraft must
exhibit enhanced stall characteristics showing it to be reluctant to
enter a spin during normal flight operations and has additional
feature that ensures survivability for the occupants.

2- Enhanced stall
Enhanced stall behaviour has to be demonstrated which means conformity
to the following items.
a. During the stall manoeuvers contained in 23.201, if an
uncontrollable downward pitch does not occur, the pitch
control must be held against the stop and controlability must be
demonstrated….roll from 15° bank to 15° bank in the other direction in
the stick full aft position.
b. If a uncontrollable downward pitch occurs, stick full aft for at
least 2 seconds after the nose pitches while maintaining
wings level whithin [sic] 15° bank. At the end of the 2 seconds,
standard stall recoverey [sic] control inputs must produce an
immediate return to unstalled flight without any tendency towards spin
entry.
c. Stall from 1.5 Vs1 maintaining a stabilised slip. The slip angle
must be equivalent to the value of a landing with an appropriate
sideslip angle (typically between 0.1 and 0.2 Vs0 crosswind
component). The roll must be controlled with the ailerons. The
stabilised slip must be maintained at constant bank angle until stall
break. During the stall, the bank angle must not exceed 60°.
d. Following an abused stall entry controllability demonstration, the
aircraft must respond immediately and normally without unreversed use
of the controls and without exceeding the temporary control forces
specified in 23.143 ( c ) to regain coordinated unstalled flight.

3- Airframe parachute system
1. The parachute must be fully deployed and a stablized descent rate
established in the same or less altitude than airplanes that are in
the same class typically take to recover from the one-turn spin
requirement of 23.221.
2. The GARD system must not be deployed before one turn or 3 seconds,
whichever takes longer, after spin initiation.

4- Emergency procedure
CRI B-2 Page 4/2
A clear emergency procedure has` to be written in the AFM which would
be one of the following ;
A- In case of a spin, deploy the parachute.
B- In case of a spin under (altitude to be determine), pull the handle
In case of a spin above (altitude to be determine), apply the normal
spin recovery. In case of no result after 5 seconds, pull the
handle.

CRI B-2 Page 5/2
Appendix 6 – FAA letter

CRI B-2 Page 6/2
Appendix 7 – Cirrus Design letter

-------------------------------------------------------------

It documents the method mentioned.


I presume you are referring to this from page four:

The aircraft recovered within one turn in all cases examined.
Recovery controls were to reduce power, neutralize ailerons, apply
full rudder opposite to spin, and to apply immediate full forward
(nose down) pitch control. Altitude loss from spin entry to
recovery ranged from 1,200 – 1,800 feet.

The POH for the SR22 had spin recovery documented, but that text was removed
in later revisions in favor of the CAPS as only method of spin recovery. My
guess would be that the lawyers made that decision.

--Galvin


It may have been removed, because the CAPS system is capable of
recovery within less than 1,000 feet*, while the control input method
documented in the block quote above requires 1,200 – 1,800 feet, and
if not performed correctly, may result in an unrecoverable flat spin:

Also from page four:

It must be assumed that the SR20 has some unrecoverable
characteristics. In the SR20 proper execution of recovery control
movements is necessary to affect recovery, and aircraft may become
unrecoverable with incorrect control inputs.


Appendix 3 provides this additional information:

CRI B-2 Page 1/2
Appendix 3 – SR20 AFM Section 3
Inadvertent Spin Entry
The SR22 [sic] is not approved for spins, and has not been tested
or certified for spin recovery characteristics. The only approved
and demonstrated method of spin recovery is activation of the
Cirrus Airframe Parachute System (See CAPS Deployment, this
section). Because of this, if the aircraft “departs controlled
flight,” the CAPS must be deployed.


So it would appear that the Cirrus SR20's spin characteristics have
not been exhaustively tested, because conventional spin recovery
techniques were found to be less than optimal in some cases, so the
SR20 was equipped with the CAPS system which afforded safety benefits
additional to spin recovery.




*.. The minimum certified altitude loss for a CAPS deployment from
a one-turn spin is 920 feet.
  #70  
Old February 6th 05, 08:15 PM
'Vejita' S. Cousin
external usenet poster
 
Posts: n/a
Default

In article ,
I hate it when people back statements up with data.


He didn't. That's hardly "NTSB database is full of them SR-20/22's" by
ANY standard.


How do you define full? For example I tried to do a search on the
Van's RV-6/7 when I was thinking about buying one and there are very few
accidents (at over 100hrs) that involve them.
 




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