RV9A in-flight breakup

A place to plan social gatherings, flying events, etc.
Post Reply
User avatar
A2022
Class D
Posts: 363
Joined: Sat Mar 05, 2022 8:52 am
Location: Cincinnati, OH
Contact:

RV9A in-flight breakup

Post by A2022 »

I saw this report about a fatal (2) accident and wondered about Oshkosh-itis. VMC into IMC seems to be the cause. pushing too far. never let get-there-itis or airplane marketing hype push you into dangerous situations. the marketing guys are doing their job to get folks pumped up (that's how they get paid), but there will always be next time. very sad, condolences to the families.

http://www.kathrynsreport.com/2022/07/v ... ident.html

RIP
Lyrics: Ben Böhmer - Slow Wave
https://youtu.be/Kgk0yKyYPL0

Image
Last edited by A2022 on Sun Sep 04, 2022 11:05 am, edited 3 times in total.
Steve Melton
RV9A, Superior O-320 (roller cams), WW 200RV prop, Dual impulse slick mags, CHT 330F, EGT 1300F, Oil pressure = 65 psi, B and C Alt, 1000+ hours
Freedom and Democracy are all that really matter.
https://www.rvplasticparts.com/

User avatar
A2022
Class D
Posts: 363
Joined: Sat Mar 05, 2022 8:52 am
Location: Cincinnati, OH
Contact:

preliminary - in-flight breakup

Post by A2022 »

preliminary report. in-flight breakup. I believe this is the 2nd RV9A to go down in a thunderstorm. possible overspeed, rudder and vertical stab separation found first, then horizontal stab and wing, then the rest of the aircraft. that is the typical pattern of an RV in-flight breakup. in an RV9, it doesn't take very long to exceed Vne in a descent. pushing too hard to get to Oshkosh. message: forget the Oshkosh marketing hype - those guys get paid to hype-it-up.

https://aviation-safety.net/wikibase/280790

this is a controlled descent and recovery in an RV9 to Vne in smooth air. Vne is reached in about 15 seconds. when the pilot is disoriented and in turbulent conditions, it could occur sooner.
https://youtu.be/2LhFZwankY0

condolences to the families.

Image

*************

the first RV9A that went down in a thunderstorm was not too far from me in Ohio. the year was 2016. message: stay out of thunderstorms in these delicate aircraft. they are total performance but not in thunderstorms. they are weak there.

Image

The vertical stabilizer and rudder were found 0.61 to 0.63 nautical miles southwest of the main wreckage, respectively, and exhibited overload signatures consistent with an in-flight breakup.

http://www.kathrynsreport.com/2016/07/v ... ident.html

https://data.ntsb.gov/carol-repgen/api/ ... /93660/pdf


Image
Last edited by A2022 on Sun Sep 04, 2022 9:51 am, edited 1 time in total.
Steve Melton
RV9A, Superior O-320 (roller cams), WW 200RV prop, Dual impulse slick mags, CHT 330F, EGT 1300F, Oil pressure = 65 psi, B and C Alt, 1000+ hours
Freedom and Democracy are all that really matter.
https://www.rvplasticparts.com/

User avatar
A2022
Class D
Posts: 363
Joined: Sat Mar 05, 2022 8:52 am
Location: Cincinnati, OH
Contact:

Re: RV9A in-flight breakup

Post by A2022 »

N192MH; it appears this aircraft was using the heavy wheelen tail strobe and had glassed in both the upper and lower fiberglass fairing. both of these actions add weight to the rudder in the worse possible places and will lower the rudder flutter speed.

wheelen tail strobe installation assembly = +1/3 lb
glassed-in tip fairings = +1/4 lb (maybe more, how do you know?)

I believe Van's should issue a SB about the rudder to avoid adding unnecessary weights that will adversely affect rudder flutter speed. folks may think they are making it better, when they are making it worse. they just don't know the fundamentals. this is serious business.

Image
Steve Melton
RV9A, Superior O-320 (roller cams), WW 200RV prop, Dual impulse slick mags, CHT 330F, EGT 1300F, Oil pressure = 65 psi, B and C Alt, 1000+ hours
Freedom and Democracy are all that really matter.
https://www.rvplasticparts.com/

Post Reply