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  #61  
Unread 03-07-10, 01:04 AM
CO_Skymaster CO_Skymaster is offline
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I had to think about that for a moment and where the forces are on the wing, but he is right. The up wing has the downward alerion deflection, so that part of the wing has the higher angle of attack and higher loading. Augh... you're taking me back to my aerodynamics classes. :-)

Karl
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  #62  
Unread 03-09-10, 11:20 AM
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N5ZX N5ZX is offline
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Questions:
The accident A/C was using rwy 32.

The debris field was distributed along a 360 heading from the departure end of the rwy indicating a right deviation from a 320 rwy heading...right wing was lower than left (right bank).

The right wing tip seperated from the right wing and seems to have peeled up and rolled over the fuselage, impacting the rear engine nacelle. This would seem to indicate that the bottom of the wing was the "leading edge", otherwise wouldnt the seperated portion have impacted further back on the A/C...like on the tail boom, etc.

The NTSB preliminary report says that the right wing spars show indications of DOWNWARD bending...the seperated portion folded UP and over....what could cause that?

The plane flew a perfect, pattern. Descended at an unacceptable speed with Flaps and gear up and spoiler apparently not deployed...they were TRYING to go fast.
15:44:19 332* 900' 120kts....I normally climb at 100
15:44:50 240* 1100' 137kts....I normally do cross-wind at about 110
15:46:50 156* 1400' 148kts....I normally start slowing to 100 around mid-field..
15:47:00 062* 600' 171kts....My base-leg is 100... 100 on final...90 over the fence....80 on the numbers (or somewhere there-abouts).

The last radar return had them on Base-leg at 600' msl (450' above Field Elevation) at 171kts and accelerating.

Max maneuvering speed for a "normal" P337 is 155kts. Max Maneuver for the Aviation Enterprises wing tip extension tanks (if empty) is placarded at 125kts.

And to make a 90 degree turn and descend 800' in 10 seconds (according to the radar sweeps) sounds like "abrupt maneuvers" to me.

Could this HARD left descending turn (forcing the right wing up) have flexed the right tip downward.... bending the spar, weakening it but still allowing the pilot to maintain the controlled high-speed low pass along the rwy until he pulled up "sharply" and the weakened spars gave-way?

Certainly not arm-chair quarterbacking....just trying to get my head around the physics and aerodynamics and yall seem to be excellent resources.

Thoughts?
Cole

Last edited by N5ZX : 03-09-10 at 10:44 PM.
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  #63  
Unread 03-10-10, 12:26 AM
jack374dn jack374dn is offline
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As I have stated in an earlier message, my super skyrocket, 374DN, @ 32" M.P., 2400 RPM, @ 2000 feet MSL, nose down 200 FPM, @ 1000 feet MSL = RED LINE [VNE]
OAT = 85 F, DP 52, SMOOTH AIR, dead still ...

Jack
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  #64  
Unread 03-14-10, 12:56 AM
CO_Skymaster CO_Skymaster is offline
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I was looking at Cessna Skymaster Videos on U-tube and came across a video of someone making a high speed low pass. I noticed that the aircraft made a sharp turn close to the ground before the pass. I wondered if this is what the pilot was trying to do when the accident occured.

http://www.youtube.com/watch?v=c3KyePDEoQQ

Karl
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  #65  
Unread 03-16-10, 01:05 PM
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Special Airworthiness Information Bulletin

Just got this from our left coast contributor

Those of you with winglets and or tip tanks should read this.
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File Type: pdf ce-10-20.pdf (49.5 KB, 1202 views)
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  #66  
Unread 03-16-10, 01:54 PM
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Cessna News Letter

There is a reference to Cessna Service Newsletter SNL06-6, FAA Approved Supplemental Type Certificates (STC’s) and FAA-PMA Approved Parts.
I am attaching the News Letter

It's interesting to note, that in 2006, they were developing SIDs.
Attached Files
File Type: pdf SNL06-6.pdf (273.1 KB, 1176 views)

Last edited by WebMaster : 03-16-10 at 02:00 PM.
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  #67  
Unread 03-17-10, 09:05 AM
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Oops

There's an oops here.
The model referenced in the statements is a T336G, when in fact the accident aircraft was a T337G. Seems a lot of people missed that.
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  #68  
Unread 03-17-10, 10:12 AM
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Dale Campbell Dale Campbell is offline
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Crash

I have already recieved a service bulletin from the FAA concerning this crash. It states the failure at station 150 in wing. They stated every one should check if you had the modification of wing extention with fuel tanks and winglets installed. They want you to check ribs, check for wrinkled skin beyond station 150 and check for smoking rivots. The crashed 337 was a G model. I was wondering if on the models G and H that have 148-150 gallon tanks you have more weight on end of wing. Do the earlier models before G have more ribs in wing at that point were the factory installed the standard 150 gallon tanks. The more weight you hang on the end of wing the more stress it adds beyond the strut support. The aircraft that crashed also had the 550 engines with turbos capable of more power and with 2 of these engines weighing over 700 pounds more that my IO-360. Add wing extension with tanks that might be full, winglets and 5 people. He was at or over gross weight. You do the math.
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  #69  
Unread 03-17-10, 04:59 PM
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hharney hharney is offline
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Dale,
The NTSB report indicates the wing severed at WS 177 not 150. The Special Airworthiness Information Bulletin (SAIB) mentioned WS 150 for inspection. 150 is the aileron attachment point and 177 is outboard one rib.

The incident aircraft was a Riley Super Sky Rocket which had the TSIO-520's not the 550's. These were rated at 300 HP each.


All,
Just a point about the SAIB, if anyone has the extended wing fuel tanks and / or the winglets make sure you inspect the areas described in the SAIB above. I suggest that you do it sooner rather than later to make sure there is no indication of potential issues as the SAIB points out.

I have just completed my annual and I have the winglets but DO NOT have extended wing fuel tanks. While performing the annual this year I had a copy of the 23 SID's that Cessna is proposing and a copy of the NTSB report on the incident aircraft in New Jersey. I can say that this annual inspection was the most thorough inspection that I have ever done. With the SID's in mind, it created a better and more thorough desire to look harder at components. With the NTSB report I was concerned about the incident with the wing and made sure that a closer inspection of those areas were covered. The first flight after the annual was Monday and the SAIB was published Tuesday. Craig and I went back to the aircraft and checked all the items on the SAIB. Everything checked ok. So if you have these mods check the areas on the SAIB.

Here is a quote from the SAIB about the incident aircraft:
The subsequent investigation revealed there have also been reports from the field of wrinkled skins,
working rivets, cracks, and loose wing tips.

This concerns me, make sure you check your aircraft for these items. Even if you don't have the mods it wouldn't hurt to take a few minutes to look this on your aircraft.
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Last edited by hharney : 03-17-10 at 05:05 PM.
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  #70  
Unread 03-19-10, 10:44 AM
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AE service letter

Here is the Aviation Enterprises Service Letter.
It only applies to those aircraft with extended wing fuel tanks.
Attached Files
File Type: pdf AE 01-11-00 Service Letter.pdf (76.2 KB, 1100 views)
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  #71  
Unread 03-19-10, 07:18 PM
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I was at my IA's hanger today as my planes annual is being finished, and I asked him if my plane experienced any discrepancies as related to "The SIDS of the week". He laughed and said don't be ridiculous. However I don't have any mods, except micro-VG's which are for goring slower, not faster.

I then asked him what a "smoked rivet" looked like. So he had me climb under the wing of a beautiful AeroStar that was in the shop and every single wing spar rivet had a 3" smoke trail behind it.

I think I will stick with my un-modified skymaster.
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  #72  
Unread 03-19-10, 09:43 PM
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It makes me wonder what "data" was produced and accepted for these wingtip extensions and goofy looking winglets, and if there was any real aerodynamic engineering involved.
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  #73  
Unread 03-23-10, 01:11 AM
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I'm not an owner nor have I ever flown in a 337. My interest in this case is a somewhat personal one as a mutual non-flying friend had introduced me to the person that was in the right seat, who I only knew by his Polish nickname as Wojtek, pronounced voitek. I flew with him twice when he was still a student pilot. My friend called me this week to tell me that that was the guy I flew with some 12 yrs ago. At the risk of being accused of and flamed for kicking the dead in their grave and patting myself on the back at the same time, I do feel vindicated that I warned my friend not to fly with him. I know this guy piled on the ratings since I've flown with him, but it was his absurd rationalizations about what was possible, permissable that I found troubling, and for my friend's sake, I cautioned him not to fly with him.

I've read all of your posts on this thread and indeed you all seem like such good eggs that I felt compelled to write what I just wrote, for I could feel your collective concern about the airworthiness of your aircraft. 337'S have their issues, which plane doesn't, but I believe in this case there is just to much evidence of people who flaunted, played fast and loose, and thumbed their noses at the laws of physics. Weight limit? Zero fuel weight? If it fits it will lift it. V speeds? Why would they put all those numbers at the end of the A/S indicator, let's see what it's like, besides it's overbuilt 150%, let's have some fun! This kind of thinking can break an EXTRA, or a F-18 for that matter.

1. 15:46:50 the airplane was at 1,400 ft msl, on a heading of 156 degrees at a ground speed of 148 knots. Then just 10 seconds later 15:47:00, the airplane was at 600 ft msl, on a heading of 062 degrees at a ground speed of 171 knots. If this radar data is to be believed, that's dropping 800 ft, accelerating 23 kts while turning 94 degrees in 10 seconds with 5 people on board. Are you kidding me?

2. I'm having a tough time untangling the various V and weight limits, with all the different variants, stc, mods, etc., so I submit this for your perusal. I found this on FlightAware. N12NA's flight from KBTV Burlington, VT to 47N Central Jersey Regional on Sept, 2009. Don't know if someone knows how to get the winds aloft data for that day, but check it out. Note the ground speeds and what in my estimation seems like a dive bomber approach. From 16500ft to 2400ft in approx 30 miles, and 6 mins. Doesn't that seem excessive. Here's the track- http://flightaware.com/live/flight/N...259ZZ/KBTV/47N
Here's the radar log- http://flightaware.com/live/flight/N...V/47N/tracklog

One last thing before I step down from my soapbox, I love aviation. Been in it for 42yrs, 20yrs as a pilot. I felt very proud to have achieved that. Human nature being what it is, I believed that it showed a special sense of competence in an individual to be able to do this. It pisses me off when jokers come along with bird brained notions and make all of us flying look like one step above the village idiot, not to mention the loss of innocent people who place their lives in our trust. Great fun that it can be, it's an unforgiving hobby we've chosen. One fool and in this case maybe two and we all get a black eye. One last thing, last annual inspection was done Feb09. Maybe, if only, could of, might have caught a gremlin, but I think the only gremlins were in the two front seats.

Peace Out
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  #74  
Unread 03-23-10, 01:16 AM
hotprop hotprop is offline
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Here's a picture of N12NA
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  #75  
Unread 03-23-10, 05:18 PM
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Hotprop

Your handle implies one of two things: 1) IFR in the ice, or 2) like hot rod. After reading your message above I assume it's not #2.

Thanks for your input, I think the members came to that same conclusion based on the reports. Sad deal. The worst of it, as you have read, we are beating up our aircraft because of it. That's just part of the passion that we all share. We are concerned about what may have happened and if there is something wrong with the mod's or the airframe. I hope we can get through this without a lot of pain.

I wouldn't always rely on flightaware log. I have seen too many stray figures in my own flights.

Thanks for the photo, it was posted on the first page of the thread too.
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