Piper Tomahawk and its spar

[Cessnaflyer 56]

I rented a Tomahawk the other day and before I flew it I was reading some owners reviews about the aircraft. They all mentioned the 11,000 or so hour airframe life restriction because of the main spar. I kept searching around and must have missed what caused this restrictions. I didn't check the AD's yet because I really don't want to look through them all for an answer ;-)

[CF104 0]

11,000 hrs is the limit imposed by Piper on their Type Certificate. You can see it here:http://www.pipertomahawk.com/TCDS%20A18SO.pdfThere's also a wing life extension kit that extends the wing life to 18,650 hrs.http://www.sterlingaviationtech.com/store/...tegory_Code=001This is also a good general website for the PA-38.http://www.pipertomahawk.com/default1.htmCheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.sstsim.com/images/team/JR.jpg

[Cessnaflyer 56]

Thanks for that type certificate, interesting read. I love the aircraft it's a shame it can't go past 11,000 hours.

[CF104 0]

>Thanks for that type certificate, interesting read. I love>the aircraft it's a shame it can't go past 11,000 hours. It can go to 18,650 hrs. You just need $3,300 for the kit and a good shop to install it.Cheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.sstsim.com/images/team/JR.jpg

[Rottenlungs 0]

How did you find the trim control? It's a kind of spring loaded thing and my experience was that it was pretty vague. Very different to the 152 where I can dial in 3 turns of nose up and consistently drop to 70kts with 1 notch flap.The Tomy I flew, ZK-EQG, was the oldest one in NZ (AFAIK) and had 10,730 hours tt when I flew it. I didn`t know there was a mod to take the hours up to 18k.CheersJamesPS, discovered that the tail tie-down hoop makes a good tailskid if you really balloon it!

[Cessnaflyer 56]

>How did you find the trim control? It's a kind of spring>loaded thing and my experience was that it was pretty vague.>Very different to the 152 where I can dial in 3 turns of nose>up and consistently drop to 70kts with 1 notch flap.Trim control on the ones I have been flying have all been the standard elevator trim controls.

[Guest Tim13]

The stall/spin section of that website is pretty interesting. I read an article in a light plane maintenance magazine many years ago that had an expose` on the Tomahawk. The article quoted former project engineers that claimed that the aircraft used for certification had beefier wings(ie more wing ribs) than the eventual production aircraft ended up using. Of course, cost was implicated as the reason for making the change after certification. These engineers claimed that the fewer ribs in the wing made it less stiff, and more susceptable to oil canning during the stall. This results in enough of a deformation of the wing shape to negatively affect the stall characteristics of the aircraft. If memory serves me, the Traumahawk was the first light GA aircraft certified under a more laid back procedure where the manufacturer sort of "self certified" with oversight by the FAA, versus the old way of the FAA guiding the manufacturer through the process step by step. Everything that I've read about the TH and Piper during this time, leads me to beleive that they took some short cuts, and turned out a poor training aircraft. It's not a bad overall plane, just not the best for a trainer, which is ironic since that was it's market.I learned in a TH, and was shocked at the difference in handling when I jumped behind the yoke of a C-152 for the first time. Both are two seat trainers, both have similar performance, but both are worlds apart when it comes to teaching a student how to fly.Tim13

[Cessnaflyer 56]

I only have about 40 hours PIC in a C152 and an even less amount of 5 PIC in a Tomahawk. I feel that the Tomahawk is probably the better trainer of the two because the characteristics are more of that of a larger airplane and feels like flying a Bonanza, just a little slower ;) . That is some interesting insight on the information about the lack of some of the ribs after the flight testing. Next time I fly the TH I think I'll have to give the wing some tapping spanwise down the camber of the wing to see how many it does have.

[Rottenlungs 0]

Hi Yeah, the trim wheel is conventional in appearance, however, IIRC there are no trim tabs on the elevator - it uses a spring force to bias the elevator to provide a trim effect. For me, I found there was a lot of hysteresis in the mechanism and trimming to the same configuration resulted in inconsistent indication from the trim position indicator.I`ve found the 152 to be mechanically better all round, though the extra room and visibility in the Tomy are great..CheersJames