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Single-Seat Accident Records (Was BD-5B)
With the current discussion in another thread regarding the accident record
of the BD-5, I thought it might be interesting to do a little more in-depth look. I decided to examine the accidents between 1 January 1990 and 13 November 2003 and do a breakdown as to relative accident/fatality rate, pilot experience, and cause of accidents. To give a little depth to the situation, I also ran the same analysis for two other single-seat homebuilts. I selected the RV-3 as an airplane with a similar "mission" as the BD-5. And I use the Fly Baby because, well, I ALREADY had the downloaded NTSB files on it. :-) DATA SOURCE: I downloaded the accident reports from the NTSB web pages for these three aircraft. In all cases, I used several variants of the names to try to avoid missing any reports. I also ran a simple search for all amateur-built accidents and amateur-built accidents with fatalities over the same period. I do not have any data indicating how many of each type of aircraft existed in each year. Therefore, I used the number of each type registered in January 2003 for the basis for some of the percentages. I used the FAA/EAA practice of only counting those airplanes which are listed as having airworthiness certificates, even though the listings are somewhat inaccurate. Thus, the following fleet-size figures are used: Fly Baby: 265 BD-5: 81 RV-3: 170 Using the January 2003 fleet size numbers is only for comparison; remember, it does not reflect the number of a given aircraft in the fleet at the time of any particular accident. When running percentages based on this fleet size, I did *not* add back the crashed airplanes into the total fleet size. This is different from my earlier, BD-5-only report, so the percentages will be slightly different. ANALYSIS METHOD: Using the NTSB reports, I extracted key features and transferred them to a database. The database included items like the type of aircraft, date of accidents, number of fatalities and injuries, the ratings held by the pilot, whether the aircraft was on its first flight, a "test flight", or whether the pilot had newly purchased the plane, and 36 separate categories for the accident cause. I would enter the NTSB primary cause as a "1" in each category, and any related events as "2"s. However, when developing the cause statistics, I ignored the primary/secondary indications and just counted whether the categorized item was a factor. I did vary from the NTSB cause determination in one kind of case: When an accident occurred after a loss of power. Often, the NTSB assigns pilot error as a cause (either primary or contributing) if the pilot in not able to safely land the aircraft after an engine failure. In my analysis, I considered only the even that *caused* the emergency; if the pilot misjudged a deadstick landing approach, I did not flag that as an accident cause. Keep in mind that the statistical base is NOT high for any of these three aircraft. We're talking 15-20 accidents over a 13-year period, here. But things are easier to compare when presented in percentages. Finally, the data presented may appear better if you switch your newsreader to a fixed-spacing font rather than variable spacing. OK, on to the results! OVERALL ACCIDENTS: Here are the total number of accidents I extracted from the NTSB online database. Again, this is the period from 1 Jan 1990 to 13 November 2003. Type Accidents fatal All Homebuilts 2881 837 Fly Baby 15 5 BD-5 22 9 RV-3 14 5 OVERALL ACCIDENT RATE: Let's look at the overall accident rate for the homebuilt fleet and the individual types. The "Accidents" is the total number of accidents vs. the number of that type on the Jan 2003 register, and the "Fatals" column is the number of accidents in which the pilot was killed. Accidents Fatals All Homebuilts 11.1% 3.2% Fly Baby 5.7% 1.9% BD-5 27.2% 11.1% RV-3 8.2% 2.9% FATAL ACCIDENTS TO TOTAL ACCIDENTS These ratios show the relative number of fatal accidents vs. the total accidents for that type. Type Fatal Rate All Homebuilts 29.1% Fly Baby 33.3% BD-5 40.9% RV-3 35.7% The number of accidents involving fatalities is one indicator of the relative crash-worthiness of a design. However, these factors do not reflect the type of accident...a structural failure at altitude is generally not survivable, no matter the design of the aircraft. PILOT QUALIFICATIONS The NTSB reports, especially the older ones, did not always list the ratings held by the accident pilot. Less than half the reports contained the pilot rating information. For the purposes of this analysis, I have presumed that the pilots whose qualifications were not listed had Private licenses. Private Comm ATP Fly Baby 80.0% 13.3% 0.0% (One unlicensed pilot) BD-5 63.6% 18.2% 18.2% RV-3 71.4% 21.4% 7.1% Again, keep in mind the small sample size here. The 7.1% for ATPs involved in RV-3 crashes represents *one* individual. AIRCRAFT TEST STATUS Occasionally, the NTSB reports indicate that the airplane was on its first flight, or was newly-purchased. Or, they may indicate that the airplane was on a "test flight." It is unknown whether other accidents actually occurred during these phases; the NTSB investigator may not have been aware of it or didn't consider that it was a significant contributor to the cause of the accident. "First flight": Aircraft specifically identified as never having flown before. "Test Phase": Aircraft identified as still in its FAA-specified test phase, or the NTSB report indicates the purpose was a test flight. "New Pilot": NTSB report says the owner had recently purchased the aircraft. First Flight Test Period New Pilot Fly Baby 0.0% 0.0% 13.3% BD-5 9.1% 22.7% 9.1% RV-3 0.0% 0.0% 21.4% For the Fly Baby, a single accident was 6.7% of the total, the BD-4 was about 4.5%, and the RV-3 was about 7.1%. ACCIDENT CAUSES As mentioned earlier, I include both the primary and any secondary causes in this list, with the exception of any pilot error occurring after a loss of power. The accident categories I use a "LOP - Non-Pilot": A loss of power that is not attributable to the pilot's actions. This could include blockage of a fuel line, magneto failure, etc. This category is also used for unexplained losses of power. "LOP - Pilot": A loss of power attributable to pilot actions...fuel exhaustion, carb ice, etc. "Pilot Judgement/ mishandling": The classic "Pilot Error" category. These factors include both cases of bad decision-making as well as those of losing control of the aircraft due to windy conditions. Keep in mind that this really isn't the only "pilot error" category..."LOP - Pilot," "Density altitude,", "Maneuvering at Low Altitude," etc. are cataloged individually and are NOT reflected here. "VFR to IFR": Basically, scud running. "Mechanical Failure - Airframe": Generally, structural failure of some sort, though not necessarily of critical structure. Includes door, canopy, panel, etc. failures. "Mechanical Failure - other": Generally failures of non-engine or fuel system accessories. Does include propeller and spinner failures. "Maneuvering Low Alt": Unnecessary low flying. Does not include cases of high-altitude flying where the terrain outclimbs the airplane. "Density Altitude": Hot/High conditions "Builder error:" Workmanship problems, deviation from instructions, etc. "Mechanical Failure - Maintenance": Failures due to mistakes while performing maintenance...leaving bolts out, etc. "Midair": Collision with another aircraft. "Inadequate Preflight": Failure to detect flawed conditions or plan the flight properly. "Inexperience": Lack of experience, either in total time or in the accident airplane. "Fire": Pre-crash fires. "Undetermined": No surviving witnesses and the wreckage is too damaged to show any potential mechanical flaws. Again, keep in mind that both primary and secondary causes are included here, so the columns won't add up to 100%. (FB is Fly Baby) FB BD-5 RV-3 LOP - Non-Pilot 20.0% 40.9% 14.3% LOP - Pilot 13.3% 0.0% 14.3% Pilot Judgment/ mishandling 13.3% 36.4% 28.6% VFR to IFR 6.7% 0.0% 7.1% Mechanical Failure - Airframe 13.3% 0.0% 21.4% Mechanical Failure - other 0.0% 0.0% 14.3% Maneuvering Low Alt 0.0% 0.0% 7.1% Density Altitude 0.0% 4.5% 0.0% Builder error 13.3% 4.5% 0.0% Mechanical Failure - Maint. 20.0% 9.1% 7.1% Midair 0.0% 0.0% 7.1% Inadequate Preflight 6.7% 0.0% 0.0% Inexperience 6.7% 18.2% 7.1% Fire 0.0% 0.0% 7.1% Undetermined 6.7% 0.0% 0.0% Percentage one accident represents: 6.7% 4.5% 7.1% The BD-5 has a loss of power accident rate twice that of the Fly Baby and almost three times of the RV-3, reflecting the design's long problems with finding a reliable powerplant. The Pilot Judgment/Mishandling categories are fairly close for the RV-3 and BD-5, but the BD-5 has trigear and the RV-3 is a taildragger. The Fly Baby, though, is half their rates, which probably reflects the BD-5/RV-3 high-performance status. The BD-5's "Inexperience" results are interesting, too. Anyway, that's what the statistics look like. Ron Wanttaja |
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Great job Ron, thanks.
Could you tell me where to find the information on the RV-3 midair? Jerry Ron Wanttaja wrote: With the current discussion in another thread regarding the accident record of the BD-5, I thought it might be interesting to do a little more in-depth look. I decided to examine the accidents between 1 January 1990 and 13 November 2003 and do a breakdown as to relative accident/fatality rate, pilot experience, and cause of accidents. To give a little depth to the situation, I also ran the same analysis for two other single-seat homebuilts. I selected the RV-3 as an airplane with a similar "mission" as the BD-5. And I use the Fly Baby because, well, I ALREADY had the downloaded NTSB files on it. :-) snip |
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On Sat, 15 Nov 2003 22:03:25 GMT, Jerry Springer
wrote: Great job Ron, thanks. Could you tell me where to find the information on the RV-3 midair? Go to: http://www.ntsb.gov/ntsb/query.asp and paste: ATL02LA012A into the NTSB accident number field, near the bottom of the form. I've pasted the full narrative below. Accident occurred as the airplanes were touching down...no injuries! Neither had seen the other, nor heard him on the radio. Ron Wanttaja ----------------------------------------- NTSB Narrative report: ATL02LA012A On November 10, 2001, an Extra-Flugzeugbau GMBH EA300/L, N2XA, registered to Aero Sport Inc., operating as a 14 CFR Part 91 demonstration flight, and a James D. Smith RV-3, N93HS, registered to a private owner, operating as a 14 CFR Part 91 personal flight, experienced a mid-air collision during landing flare touchdown at the St. Augustine Airport (SGJ), St. Augustine, Florida. Visual meteorological conditions prevailed and no flight plan was filed for either airplane. N2XA sustained minor damage and N93HS sustained substantial damage. The airline transport-rated pilot and private pilot-rated passenger on N2XA reported no injuries. The commercial pilot on N93HS reported no injuries. N2XA departed from SGJ about 30 minutes before the accident. N93HS departed from Haller Airpark (7FL4), Green Cove Springs, Florida, about 30 minutes before the accident. The pilot of N2XA stated he departed SGJ about 30 minutes before the accident to conduct a demonstration flight to a prospective buyer. They flew to a training area located about 20 miles southwest of SGJ and he demonstrated the airplane. Upon completion of the maneuvers, they returned to SGJ. They attempted radio contact with SGJ UNICOM was which uneventful, however they overheard other airplanes indicating that they were landing to runway 02. They continued toward the airport making radio calls in the blind concerning their position and made a 45-degree entry for a 800 feet left downwind to runway 02 behind a Cessna airplane. The Cessna landed and reported clearing the active runway while they were turning from base to final approach. The left wing of his airplane was down for a required left crosswind landing. He started to flare the airplane just past the numbers and felt a "bump" similar to a hard landing and observed what he thought was a wheel pan go past the canopy of his airplane. At first he thought he would make a go-around but elected to land straight ahead. Upon completion of the landing, he turned his airplane 90-degrees on the runway and observed an RV-3 on the runway. He continued turning his airplane and back taxied down the runway to the RV-3, stopped, and shut his airplane down. At no time during his entry into the traffic pattern or during his approach did he or his passenger hear any radio communication from the RV-3 pilot. The pilot of N93HS stated he departed 7FL4 about 30 minutes before the accident. He approached SGJ from the northwest and attempted to contact SGJ UNICOM which was uneventful. He overheard other airplane pilot's on the UNICOM radio (A Cessna and a Piper pilot indicated they were landing to runway 02 and a Falcon jet pilot indicated he was landing to runway 31.) He decided to over-fly the airport at 1,500 feet to verify the wind condition and speed. He over flew the airport and entered a left downwind at 900 feet. While on final approach for runway 02, he observed the Falcon jet back-taxing down runway 02. He initiated a go-around, reentered left traffic at 900 feet behind a Cessna. The Cessna landed and cleared the active runway. He reported his position on UNICOM on short final. As the wheels of his airplane were touching down on the runway, he immediately felt an impact coming from above. He looked and observed the Extra on the runway. He stopped his airplane and exited unassisted. At no time while he was in the traffic pattern did he see or hear the Extra pilot on the UNICOM frequency. Examination of N93HS by the FAA revealed that both wheels of N2XA struck the top of N93HS left wing and left elevator. In addition, N2XA right wing struck the top of N93HS vertical stabilizer and canopy. (For additional information see FAA Aviation Safety Inspector Statement an attachment to this report.) Review of 14 CFR Part 91.113 Right-of way rules states in paragraph (g) Landing...."When two or more aircraft are approaching an airport for the purpose of landing, the aircraft at the lower altitude has the right-of-way." |
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In article , Ron Wanttaja
writes: Anyway, that's what the statistics look like. Ron Wanttaja Great work and information...Thanks Ron. Bob Reed www.kisbuild.r-a-reed-assoc.com (KIS Builders Site) KIS Cruiser in progress...Slow but steady progress.... "Ladies and Gentlemen, take my advice, pull down your pants and Slide on the Ice!" (M.A.S.H. Sidney Freedman) |
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On Sat, 15 Nov 2003 20:44:32 GMT, Ron Wanttaja
wrote: With the current discussion in another thread regarding the accident record of the BD-5, it would be interesting to see the correlation between survivability and stall speed. I suspect that there is more of a correlation between those two factors than which design was involved. Stealth Pilot |
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On Sat, 15 Nov 2003 22:03:25 GMT, Jerry Springer
wrote: Great job Ron, thanks. Could you tell me where to find the information on the RV-3 midair? Jerry ++++++++++++++++++++++++++++++++++++++ I'm surprised it's just ONE. I could report several near misses a week. Even on short finals of 500 feet, too many doods take off directly in front of me. The answer is ALWAYS the same. Sorry, I just didn't SEE you. The last really frightening near miss was with a T-6 at 4500 feet. I was westbound. The T-6, going east. Yes, he could have been climbing through 4500, but when I made a 180 and overtook him...... Yep, still sitting at 4500 feet and totally oblivious to me now safely off his left wing. He and his passenger were having a grand time just yucking it up from what could be observed as total indifference to air traffic and the VFR altitude scheme. At 5500 feet or more, the sky has been relatively event free over the last three years and 500 hours. So, that's where I can be found on flights even as short as 40 miles.... and I try to stay in the hangar for less than 50 miles. A 50 mile flight is usually around 20 minutes on the tach. I suspect a WHITE RV3 can be equated as just another invisible motorcycle... even though strobes flash anytime the engine is running. Perhaps, a set of H.I.D. headlights flashing high beams are the ticket. However, they won't help when the other guy has his head buried in the cockpit... or up his arse. Barnyard BOb -- super swivel head |
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On Sat, 15 Nov 2003 20:44:32 GMT, Ron Wanttaja wrote:
OVERALL ACCIDENT RATE: Let's look at the overall accident rate for the homebuilt fleet and the individual types. The "Accidents" is the total number of accidents vs. the number of that type on the Jan 2003 register, and the "Fatals" column is the number of accidents in which the pilot was killed. Accidents Fatals All Homebuilts 11.1% 3.2% Fly Baby 5.7% 1.9% BD-5 27.2% 11.1% RV-3 8.2% 2.9% An email discussion with a fellow netter pointed out that these figures are liable to misinterpretation. The rates shown above are over the 14-year period of the data collected, and are not *ANNUAL* rates! Divide by 14 to get the average annual accident and fatality rate. Or, heck, just read it off this table: Acc. Fatals 1990 1.33% 0.45% 1991 1.17% 0.38% 1992 1.36% 0.44% 1993 1.32% 0.36% 1994 1.24% 0.34% 1995 1.29% 0.43% 1996 1.14% 0.32% 1997 0.99% 0.34% 1998 1.19% 0.34% 1999 1.09% 0.30% 2000 1.14% 0.26% Ron Wanttaja |
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On Sun, 16 Nov 2003 18:28:58 +0000, Ron Wanttaja wrote:
... The rates shown above are over the 14-year period of the data collected, and are not *ANNUAL* rates! Divide by 14 to get the average annual accident and fatality rate. Or, heck, just read it off this table: ... Thanks, Ron! You used the number of registered aircrafts as of January 2003, right? How many aircrafts do you think have been removed from the register during these 14 years? If this is a substantial number, they would push the accident rate further down. - Holger |
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On Sun, 16 Nov 2003 11:16:39 -0800, "Holger Stephan"
wrote: On Sun, 16 Nov 2003 18:28:58 +0000, Ron Wanttaja wrote: ... The rates shown above are over the 14-year period of the data collected, and are not *ANNUAL* rates! Divide by 14 to get the average annual accident and fatality rate. Or, heck, just read it off this table: Thanks, Ron! You used the number of registered aircrafts as of January 2003, right? How many aircrafts do you think have been removed from the register during these 14 years? If this is a substantial number, they would push the accident rate further down. That was so for the 14-year rate in the first posting, but for the annual-rate table, I used the number of homebuilts that the EAA said was on the registry for that year. So the per-year data should be fairly accurate. I got that data several years ago, when I was researching my homebuilt registration-statistics articles for KITPLANES. Here's the breakdown of the per-year registration, with the net gain over the previous year. "Total" is the total number of homebuilts on the registry that year, "Net" is the net percentage increase in the number of homebuilts over the previous year. Year Total Net 1990 13432 6.1% 1991 14227 5.9% 1992 14916 4.8% 1993 15068 1.0% 1994 15995 6.2% 1995 16876 5.5% 1996 17837 5.7% 1997 18732 5.0% 1998 19643 4.9% 1999 20494 4.3% 2000 21087 2.9% While the figures through 2000 were declining, they came up in subsequent years: 2001 22186 5.2% 2002 24496 10.4% 2003 25656 4.7% 5.2% was the average annual net increase between 1990 and 2003. I took a cut at adding the accident aircraft back into the totals to get an approximation of the number of new homebuilts registered that year (the net value above stems from the new-registered homebuilts minus those removed from the registry in a given year). However, the FAA doesn't automatically remove crashed planes from the registry, so the approximation wouldn't work. Ron Wanttaja |
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On Sun, 16 Nov 2003 21:00:00 +0000, Ron Wanttaja wrote:
... That was so for the 14-year rate in the first posting, but for the annual-rate table, I used the number of homebuilts that the EAA said was on the registry for that year. So the per-year data should be fairly accurate. Ah - then it is good, thanks Ron. Of course, for us as individuals, the probability of driving a vehicle that will kill us may be more important than the probability of this happening during a certain year within the 14 year period. - Holger |
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