OK, odd/unique question of the day...

[WKTaylor]

Confused in the Midwest...

I was on the freeway driving-along at 80-MPH as usual... when I came upon a PU truck hauling a long trailer with an AG plane [Piper Pawnee?] doing roughly 70-MPH. That day we had gusting quartering-cross winds from the RT-Front up to ~25-MPH and it was uncomfortable. Obviously... for a flyable aircraft... trailering a few hundred miles seems stupid... so I assumed the aircraft was non-flyable and/or needed to travel a really long distance.

The fuselage was on its main landing gear with the tail wheel elevated ~4-ft [~level attitude], which allowed the wings to be stacked under the aft fuselage... with supports, tiedowns and visible padding. Also, the prop had been removed [not visible]. Otherwise the fuselage had the horizontal stabs and elevators/rudder installed.

What struck me as very odd was that I was NOT expecting the fuselage to be loaded backwards on the trailer... opposite to the rolling direction... for a bunch of reasons.

IF the fuselage had been pointed forward the aerodynamics would have been optimized to the 'normal' flight-neutral orientation. Also the heavy engine forward would benefit trailering center-of-gravity. AND the V-Stab/rudder might tend to be stabilizing in normal trailering. HENCE... fuselage-forward seemed more logical for trailering stability and minimizing air-loads on the stabs and elevator/rudder, than the 'backwards' loading. Right??? Also, as it was oriented, I noted that the trailing edges of the elevators/rudders [which had mechanical/external gust-locks in place] were visibly shaking/buffeting... which REALLY bugged me.

The only logical reasons for loading the aircraft backwards on the trailer seemed to be quick on-off loading: wings first; then lift the tailwheel over the wings while rolling the fuselage backwards into position. AND reverse the process for off-loading.

But the forward orientation [NOT DONE], still seems to be a safer over-all loading... with lower potential for damage, less drag, less buffet, etc... for a long trip. I really wanted to ask the driver... WHY??? but I just gawked passing-by.

Since I've rarely trailered GA Acft, this all seemed wrong. Any comments/observations/humor???

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

 

[rb1957]

I agree with maybe tail first makes it easier to offload. My initial thought is tail first is a more faired shape on the trailer (narrow tail opening to the larger nose).

Most likely I suspect that was just the way it ended up on the trailer without too much thought going into it.

another day in paradise, or is paradise one day closer ?

 

[btrueblood]

Worrisome - everything in the linkage train to the rudder and ailerons will need a close inspection. Wonder if the rudder survived the trip (didn't snap off)? I'd add that they likely pulled (come-along winch?) the plane onto the trailer by the tailwheel. Which, if it was a carrier-landing plane, would be less worrisome, but I doubt an ag plane's tail wheel is stressed for that kind of load.

 

[3DDave]

Same reason people put the mattress on top of the box spring on the roof of cars - leading to them fold up by the oncoming air stream when putting the mattress on first would cushion the roof and the box spring would keep it all flat. Wouldn't want to get roof dust on the mattress I suppose.

 

[WKTaylor]

For clarity... the Acft was tied-down 'in-the-open' on a long/conventional [not custom] flat-bed trailer.

Anyone know of FAA [AC, etc], MIL, etc document for trailering hauling a disassembled/partially-disassembled GA Acft?

For all MIL Acft, there is [usually] 'adequate' technical data for crash recovery and ground-transportation of [every specific-type] recovered Acft/major-Assys.

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

 

[Kwan]

Maybe they were thinking more of weight distribution on the trailer? Just a guess.

 

[WKTaylor]

K...

Trailers with the CG forward of the wheels [closer to the towing pintle], is typically a more stable rolling configuration.

The engine + the heavily reinforced forward fuselage and cockpit and spray hopper/tank [AG Acft, crashworthy] are concentrated forward.

Come to think about it, the trailer seemed pretty stable.

Still it bothers me thinking of an aircraft being towed backwards at high speeds.

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

 

[rb1957]

presumably the ground gust locks were on.

another day in paradise, or is paradise one day closer ?

 

[LiftDivergence]

If I were to do this I would want to ask the manufacturer what their assumptions were for analysis. Although this is a Part 23 aircraft, an analysis complying with CFF Title 14 23.2220 should have been performed. I would think this would include some assumption for peak loads and fatigue loads from handling and ground transport, which means they will have assumed a certain, hopefully conservative manner or transport.

But I feel it is unlikely that any OEM would have considered long-haul trailer transport spectra in their analysis.

Still, the first step for them should have been to contact the OEM and ask how to do it. There might be a specific manual. I hope they did that.

Keep em' Flying
//Fight Corrosion!

 

[verymadmac]

If it was a Piper Pawnee, its cert basis is CAR 8, not even CAR 3 (I knew of CAM 8 but not CAR 8).

The tail feathers are welded steel fabric, these in practice will typically die due to corrosion from what its spraying / spreading or water ingress from the tail wheel if it fly's off grass strips. I was told a story about the chemicals being sprayed on palm oil plantations being able to eat though the top of a 4130 oleo leg overnight (it wasn't Pawnee).