Cirrus... is it time for certification review?

On Sat, 28 Oct 2006 17:10:46 GMT, wrote:

If you assume that each aircraft went into service the year of its
airworthiness date, you can get the fleet size by year:

Actually, that date (fields 229-236) relates more to the current owner, than the
manufacture date. My airplane, for example, was built in 1982 but the
Certificate Issue Date is when I registered the aircraft in 1996.

Fields 52-55 contain the official "Year Manufactured." Unless the FAA has
revamped its file format, in which case I am going to be well and truly ticked
off (since I have a ton of queries, etc. that would have to be altered to match
while maintaining their compatibility with previous years).

The effect of using the Certificate Issue Date would be to skew the results
towards later years, since a, say 1998 plane sold to someone in 2004 would show
as a 2004 model.

Nice idea, though...re-run your query using the Year Manufactured, and let's
have another look at the data.

Ron Wanttaja

Ron Wanttaja wrote:
On Sat, 28 Oct 2006 17:10:46 GMT, wrote:
If you assume that each aircraft went into service the year of its
airworthiness date, you can get the fleet size by year:

Actually, that date (fields 229-236) relates more to the current owner,
than the manufacture date.

That column is labeled as "certificate issue date" in the FAA database
and I agree that it changes more often. That's not what I used, though -
I used the "airworthiness date", positions 266-273. I know of a couple
of aircraft that have changed hands a few times, and the certificate
issue date usually tracks the latest change of ownership, but the
airworthiness date usually corresponds to the original year of
manufacture.

Fields 52-55 contain the official "Year Manufactured."

Yep, it's still there. I just didn't think of using it when I compiled
the data the first time.

Nice idea, though...re-run your query using the Year Manufactured, and
let's have another look at the data.

Here it is, noted with "YOM". I have included the data from my first
post, noted with "A/W", for comparison.

Total Cirrus Design SR-20 entries in the master file: 597
Total Cirrus Design SR-22 entries in the master file: 2022

SR-20 entries in master file, listed by airworthiness date and by year
of manufactu

A/W YOM
blank 39 39
1981 1 1
1995 0 1
1997 1 0
1998 0 3
1999 5 8
2000 78 78
2001 46 45
2002 84 84
2003 96 94
2004 78 77
2005 86 87
2006 83 80

If you assume that each aircraft went into service the year of its
airworthiness date or in its year of manufacture, you can get the
fleet size by year:

End Fleet size by
of A/W YOM
1997 2 2
1998 2 5
1999 7 13
2000 85 91
2001 131 136
2002 215 220
2003 311 314
2004 389 391
2005 475 478
2006 558 558 (through early October)

SR-22 entries in master file, listed by airworthiness date and by year
of manufactu

A/W YOM
blank 174 175
2001 121 126
2002 262 267
2003 304 307
2004 431 430
2005 442 445
2006 288 272

Fleet size by year:

End Fleet size by
of A/W YOM
2001 121 126
2002 383 393
2003 687 700
2004 1118 1130
2005 1560 1575
2006 1848 1847 (through early October)

As a comparison, I did the same queries for the Cessna 172, including
the models 172, 172[ABCDEFGHIJKLMNPQRS], 172RG, P172D, R172[EGHJK],
T172, and CE-172-R172. Because this covers a much longer period of
time, some of the assumptions above are not as likely to be valid.

Total Cessna 172 entries in the master file: 26697

Cessna 172 entries in master file, listed by airworthiness date and by
year of manufactu

A/W YOM
blank 1825 1040
garbled 13 57
1955 79 107
1956 780 956
1957 540 583
1958 447 543
1959 517 566
1960 494 581
1961 457 493
1962 448 509
1963 608 678
1964 782 862
1965 901 1010
1966 909 1069
1967 507 569
1968 765 912
1969 721 708
1970 438 483
1971 463 476
1972 625 658
1973 979 1023
1974 1065 1149
1975 1202 1313
1976 1387 1468
1977 1430 1443
1978 1289 1368
1979 1294 1257
1980 880 811
1981 725 691
1982 248 222
1983 163 87
1984 159 143
1985 157 180
1986 97 81
1987 23 0
1988 27 3
1989 41 0
1990 42 0
1991 21 0
1992 38 0
1993 49 0
1994 41 1
1995 48 0
1996 48 1
1997 228 191
1998 344 293
1999 381 355
2000 385 353
2001 295 267
2002 291 248
2003 277 244
2004 216 181
2005 312 292
2006 196 170

Fleet size by year:

End Fleet size by
of A/W YOM
1955 79 107
1956 859 1063
1957 1399 1646
1958 1846 2189
1959 2363 2755
1960 2857 3336
1961 3314 3829
1962 3762 4338
1963 4370 5016
1964 5152 5878
1965 6053 6888
1966 6962 7957
1967 7469 8526
1968 8234 9438
1969 8955 10146
1970 9393 10629
1971 9856 11105
1972 10481 11763
1973 11460 12786
1974 12525 13935
1975 13727 15248
1976 15114 16716
1977 16544 18159
1978 17833 19527
1979 19127 20784
1980 20007 21595
1981 20732 22286
1982 20980 22508
1983 21143 22595
1984 21302 22738
1985 21459 22918
1986 21556 22999
1987 21579 22999
1988 21606 23002
1989 21647 23002
1990 21689 23002
1991 21710 23002
1992 21748 23002
1993 21797 23002
1994 21838 23003
1995 21886 23003
1996 21934 23004
1997 22162 23195
1998 22506 23488
1999 22887 23843
2000 23272 24196
2001 23567 24463
2002 23858 24711
2003 24135 24955
2004 24351 25136
2005 24663 25428
2006 24859 25598 (through early October)

John Smith posted the following:

Accidents and incidents (from theFAA and NTSB databases)
1998 2000 2001 2002 2003 2004 2005 2006
SR20 1 0 2 3 0 1 2 7
SR22 - - 2 2 3 8 12 15

Using that data along with the fleet size data:

SR-20

Fleet % accidents
End size by Acci- by
of A/W YOM dents A/W YOM
1997 2 2 0 0 0
1998 2 5 1 50 20
1999 7 13 0 0 0
2000 85 91 0 0 0
2001 131 136 2 1.5 1.5
2002 215 220 3 1.4 1.3
2003 311 314 0 0 0
2004 389 391 1 0.26 0.26
2005 475 478 2 0.42 0.42
2006 558 558 7 1.3 1.3 (through early October)

SR-22

Fleet % accidents
End size by Acci- by
of A/W YOM dents A/W YOM
2001 121 126 2 1.7 1.6
2002 383 393 2 0.52 0.51
2003 687 700 3 0.44 0.43
2004 1118 1130 8 0.72 0.71
2005 1560 1575 12 0.77 0.76
2006 1848 1847 15 0.81 0.81 (through early October)

Combined SR-20 and SR-22

Fleet % accidents
End size by Acci- by
of A/W YOM dents A/W YOM
1997 2 2 0 0 0
1998 2 5 1 50 20
1999 7 13 0 0 0
2000 85 91 0 0 0
2001 252 262 4 1.6 1.5
2002 598 613 5 0.84 0.82
2003 998 1014 3 0.30 0.30
2004 1507 1521 9 0.59 0.59
2005 2035 2053 14 0.69 0.68
2006 2406 2405 21 0.87 0.87 (through early October)

Finally, taking the combined SR-20 and SR-22 data for 2001-2006, and
applying it to the 172 fleet size, we get an approximate number of
accidents and incidents that would be expected from the 172 fleet, if
the 172 and SR-20/22 have about the same safety record:

Cessna 172

Fleet Expected number of
End size by accidents by
of A/W YOM A/W YOM
2001 23567 24463 374 373
2002 23858 24711 199 202
2003 24135 24955 72.6 73.8
2004 24351 25136 145 149
2005 24663 25428 170 173
2006 24859 25598 217 224 (through early October)

Matt Roberds

I hate to tell you guys this but you better look more carefully. I am a
mechanical engineering student at a very well known and respected
engineering university (I won't comment on which one because I don't feel
it is ethically correct for this letter). I am currently working full time
in the field of mechanical engineering (not aeronautics yet) and I have
only begun to research a project for an engineering reliability report and
already some pretty clear facts are starting to pop up. It seems that
pilots enter turbulence or icing conditions and that starts to cause
delamination problems with Cirrus's high tech polymer/foam shell.
Hypothetically what might happen next is the pilots try like hell to get
the things under control while they are falling apart in the sky. Again,
hypothesizing, they might try rapid maneuver's to get the plane that is
now falling apart under control and end up stalling out the engine. They
are now completely losing it and instead of trying to glide down to a safe
height and speed to deploy the parachute they deploy at high altitudes and
speeds and the parachute rips away. Who knows maybe they can't get the
plane under enough control to safely deploy the parachute, after all, if
the plane is in the process of delaminating itself (i.e. layers of polymer
ripping away) maybe it is not possible. Now I am not a pilot and as I said
my report is not complete but I can tell you that maybe some people better
start asking the right questions like why is this thing delaminating under
mildly icy conditions. I mean most of these pilots in these accidents were
trying to get away from the clouds and some of them had the de-icing
option?????? Why have a de-icing option if it doesn't work - and
typically most mechanical designs are designed to fail slowly to allow
time to take alternative, life saving action. It seems this failure is
happening way too quickly and without enough of a safety factor for the
possible working environment. I personally love the look and the
"high-tech" of the plane but if I were a pilot this delamination thing
would have me spooked. You guys as pilots should really check out the
NTSB site (http://www.ntsb.gov) before forming an opinion. Of course, as
I said as an engineer I would decline to comment rather than get my rear
in a sling but, as a concerned citizen, you guys should do some more
research before endorsing this plane. Oh by the way the plane does have a
33% higher failure ratio than other planes in the competing class
(http://www.newsday.com/news/local/ne...-nynews-print).
Again, obviously I really don't know what I am talking about, this is not
an official statement, and all the other disclaimers I can possibly
include but just some information I thought you guys might want to know.

Anonymous Mechanical Engineering Student (senior)

Anonymous Engineering Student

____________________________________
Posted via Aviatorlive.com
http://www.aviatorlive.com

On Sun, 05 Nov 2006 22:24:05 -0600, "anonymousengineeringstudent"
wrote:

... Again,
hypothesizing, they might try rapid maneuver's to get the plane that is
now falling apart under control and end up stalling out the engine.
^^^^^^^^^^^^^^^^^^^^^^^^
You do realize this costs you any credibility about aeronautical matters, right?

I personally love the look and the
"high-tech" of the plane but if I were a pilot this delamination thing
would have me spooked. You guys as pilots should really check out the
NTSB site (http://www.ntsb.gov) before forming an opinion.

I used the NTSB accident page to run a search for Cirrus accidents where the
words "delaminate", "delamination," or "delaminated" appear. I found just one
hit (DEN06FA114) where, by the context, it appears that the parts delaminated on
impact.

In which other accidents did delamination occur?

Ron Wanttaja

On Sun, 05 Nov 2006 20:42:59 -0800, Ron Wanttaja
wrote:

On Sun, 05 Nov 2006 22:24:05 -0600, "anonymousengineeringstudent"
wrote:

... Again,
hypothesizing, they might try rapid maneuver's to get the plane that is
now falling apart under control and end up stalling out the engine.
^^^^^^^^^^^^^^^^^^^^^^^^
You do realize this costs you any credibility about aeronautical matters, right?

I think it's sung to the tune of "a trolling we will go, a trolling we
will go..."


I personally love the look and the
"high-tech" of the plane but if I were a pilot this delamination thing
would have me spooked. You guys as pilots should really check out the
NTSB site (http://www.ntsb.gov) before forming an opinion.

I used the NTSB accident page to run a search for Cirrus accidents where the
words "delaminate", "delamination," or "delaminated" appear. I found just one
hit (DEN06FA114) where, by the context, it appears that the parts delaminated on
impact.

Where it's obvious it was not strong enough to withstand the g-forces
of hitting something solid at some where between 150 and 200 MPH.

In which other accidents did delamination occur?

Ron Wanttaja
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

...turbulence or icing conditions and that starts to cause
delamination problems with Cirrus's high tech polymer/foam shell.

Cite? Upon what do you base these "pretty clear facts"?

and end up stalling out the engine.

What does the wing delaminating have to do with the engine? And what
does "stall" mean in this context?

To a pilot, these words have different meanings.

Oh by the way the plane does have a 33% higher failure
ratio than other planes in the competing class...

Newsday is hardly a reliable source of engineering statistics. And for
an engineering student at a well known and respected university to use
"33% higher failure ratio" (with no numerator or denomenator specified)
is exceptionally sloppy. Perhaps you mean "rate", in which case you
still need to specify "per what" if you want to say something meaningful.

I suspect you mean well, but more care in your dissertation would be
appropriate here.

Jose
--
"Never trust anything that can think for itself, if you can't see where
it keeps its brain." (chapter 10 of book 3 - Harry Potter).
for Email, make the obvious change in the address.

anonymousengineeringstudent wrote:
I am a mechanical engineering student at a very well known and
respected engineering university (I won't comment on which one
because I don't feel it is ethically correct for this letter).

If there's a Computer Science department at your school, or an IT
department that runs the school's computers, you probably want to talk
to them. They should be able to tell you ways to post to Usenet that
can help hide the fact that you're probably posting from a Comcast
cable modem in New Jersey, 68.46.165.176 or
c-68-46-165-176.hsd1.nj.comcast.net .

I am currently working full time in the field of mechanical
engineering (not aeronautics yet) and I have only begun to research
a project for an engineering reliability report and already some
pretty clear facts are starting to pop up.

Assuming for the moment that you are in New Jersey: Both Princeton and
Rugters list departments or degree programs in "mechanical and aerospace
engineering", which is a slightly different phrasing than "aeronautics".
NJIT and Stevens simply call their programs "mechanical engineering".
Of course, you could be attending some other school in New Jersey, or a
school in a nearby state. Or, maybe you aren't in or near New Jersey at
all.

Organization: Aviatorlive.com

This site appears to be a sponge site, that is simply a "Usenet for
dummies" web gateway to r.a.p, plus the obligatory Google ads. Running
a search on that site does find your post, but because of the completely
broken threading in the web interface, it won't actually pull up there.

Headers as received he

---
From Sun Nov 5 23:02:54 2006
Path: be01.lga!hwmnpeer02.lga!hw-filter.lga!hwmnpeer01.lga!news.highwinds-media.com!news.glorb.com!border1.nntp.dca.giganews .com!nntp.giganews.com!local01.nntp.dca.giganews.c om!news.giganews.com.POSTED!not-for-mail
NNTP-Posting-Date: Sun, 05 Nov 2006 22:24:05 -0600
From: "anonymousengineeringstudent"
Newsgroups: rec.aviation.piloting
Subject: Cirrus... is it time for certification review?
Organization: Aviatorlive.com
User-Agent: Newsraptor Gateway 1.0
Mime-Version: 1.0
Content-Type: text/plain; charset="ISO-8859-1"
Content-Transfer-Encoding: 8bit
Message-ID: m
X-HTTP-Posting-Host: 68.46.165.176
References:
Date: Sun, 05 Nov 2006 22:24:05 -0600
Lines: 47
X-Trace: sv3-zpDi1mhdPPFjMFKrHGms6+kIMMVeswZVBPi93nZx5d/IAs+TTdeGh3cbCqbGz93LBU3oadKN78vD47Y!aNAhtBVFu9wBs 907rLTgQqGuho7Ls1PplABHQjoAK+55wVkAGFvI1FxOFttUzcF gpCujXLJZZe6Y
X-Complaints-To:
X-DMCA-Notifications: http://www.giganews.com/info/dmca.html
X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers
X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly
X-Postfilter: 1.3.32
Xref: Hurricane-Charley rec.aviation.piloting:171176
X-Received-Date: Sun, 05 Nov 2006 21:24:06 MST (be01.lga)
---

Matt Roberds

anonymousengineeringstudent wrote:
I hate to tell you guys this but you better look more carefully. I am a
mechanical engineering student at a very well known and respected
engineering university (I won't comment on which one because I don't feel
it is ethically correct for this letter).

Or more likely, you don't want your professor to find out about your
"thought" process and end up having to become a liberal arts major...

Again, obviously I really don't know what I am talking about

Oh, we figured that out pretty damn quickly from reading your post...
Hmmm... You would happen to be a WebTV or AOL newbie, would you?

Anonymousengineeringstudent,

Anonymous Mechanical Engineering Student


'nuff said...

--
Thomas Borchert (EDDH)