Freight tiedown to Cessna seat rails
Thread Starter
Freight tiedown to Cessna seat rails
Hi brains trust
Trying to work out how to safely take a heap of camping gear on a trip in the 210. Removing middle row seats.
I see there are some proprietary tie down clamps available (depending on who one speaks to if available means unavailable or not)
These clamp to the seat rails and allow loads to be tied down there. They are around $100 each. Not cheap given maybe 4 required.
Anyone have any better ideas? Yes am using seat belt mounts.
Anyone got any they would like to part with?
Trying to work out how to safely take a heap of camping gear on a trip in the 210. Removing middle row seats.
I see there are some proprietary tie down clamps available (depending on who one speaks to if available means unavailable or not)
These clamp to the seat rails and allow loads to be tied down there. They are around $100 each. Not cheap given maybe 4 required.
Anyone have any better ideas? Yes am using seat belt mounts.
Anyone got any they would like to part with?
This suggestion may or may not be in conflict with CASA. My experience comes from road vehicle Australian Design Rule certification.
Firstly, aircraft seat belts wouldn't go 1/3 the way toward meeting vehicle safety requirements. Don't believe me? Look at the size of the bolt holding then to the airframe bracket. Car seatbelts use a 7/16 inch grade 10 bolt (grade 10 is a higher grade than aircraft AN).
This is relevant because it sets the benchmark of how well you need to tie things down. Rule of thumb for a car is 20g.
Secondly, why do you need to tie things down at all? Accident? Things down low on the floor will be restrained by the seats in front. Other things, maybe if you constrain them for a 10g impact then the 5kg bag needs to be held by something that will support 50kg. I reckon 2 strands of kitchen twine will just about do that!
If you want to constrain the items in turbulence, then you only need probably 2g.
Personally, I'd go to supercheap and buy some of the 25mm wide webbing cam lock straps and put them though the seatbelt fitting slots.
Most camping stuff is soft. I'd put the heavy, hard surface stuff on the bottom maybe with some dedicated straps then the soft stuff on top with maybe another strap on top.
If that doesn't do it, you might review if you are really going camping - or moving house
Firstly, aircraft seat belts wouldn't go 1/3 the way toward meeting vehicle safety requirements. Don't believe me? Look at the size of the bolt holding then to the airframe bracket. Car seatbelts use a 7/16 inch grade 10 bolt (grade 10 is a higher grade than aircraft AN).
This is relevant because it sets the benchmark of how well you need to tie things down. Rule of thumb for a car is 20g.
Secondly, why do you need to tie things down at all? Accident? Things down low on the floor will be restrained by the seats in front. Other things, maybe if you constrain them for a 10g impact then the 5kg bag needs to be held by something that will support 50kg. I reckon 2 strands of kitchen twine will just about do that!
If you want to constrain the items in turbulence, then you only need probably 2g.
Personally, I'd go to supercheap and buy some of the 25mm wide webbing cam lock straps and put them though the seatbelt fitting slots.
Most camping stuff is soft. I'd put the heavy, hard surface stuff on the bottom maybe with some dedicated straps then the soft stuff on top with maybe another strap on top.
If that doesn't do it, you might review if you are really going camping - or moving house
Good question, if you can work the CASA requirements out let me know please! I certainly can't and I have asked this question many times, with no logical and practical response.........
I suggest you use your own best judgement. Don't ask an FOI for god sake, unless you know him/her reasonably well!!!!
Good luck in getting a defiant and practical answer in terms of compliance with what ever CASA require.
I suggest you use your own best judgement. Don't ask an FOI for god sake, unless you know him/her reasonably well!!!!
Good luck in getting a defiant and practical answer in terms of compliance with what ever CASA require.
Last edited by Duck Pilot; 31st May 2016 at 09:23.
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There's no such thing as a Grade 10 bolt. With regard to SAE hardware standards, there are Grade 2, Grade 3, Grade 5 and Grade 8 bolts.
Grade 2 and Grade 3 are commonly known as "mild steel" bolts and have only moderate strength, being made of simple low or medium carbon steel.
Grade 5 are commonly called "high tensile" and are made of medium carbon steel, quenched and tempered. They have a minimum tensile strength of 120,000psi.
Grade 8 fasteners are the strongest of the SAE ratings, being made of heat-treated low alloy steel and meeting a minimum of 150,000psi tensile strength.
Grade 5 fasteners can be recognised by the 3 dashes on the head of the fastener. Grade 8 fasteners are recognised by the 6 dashes on their heads.
All automotive seatbelt hardware I have ever seen (that's quite a bit) utilises Grade 8 fasteners.
Some manufacturers rate their hardware higher than Grade 8 - but this is not recognised by the SAE.
Caterpillar rate their crawler tractor track shoe bolts at Grade 9 and 180,000psi tensile strength, but this is a Caterpillar rating, not SAE.
Caterpillar quite often refuse to adopt SAE ratings and produce their own standards.
Unbrako produce alloy steel socket head (Allen head) capscrews that are rated at a consistent 190,000psi tensile strength, when the usual standard for U.S.-made socket head capscrews is 170,000-180,000psi tensile strength.
There is no SAE Grade for the high strength alloy steel capscrews.
Metric hardware is rated as Classes, not Grades. Metric Classes are Class 8.8, CLass 10.9 and Class 12.9.
These "classes" are approximately aligned in tensile strength with the SAE Grade 5, Grade 8, and Grade 9.
Aircraft AN bolts are rated at 125,000psi tensile strength, thus making them only slightly stronger than SAE Grade 5 hardware.
25mm webbing cam lock straps are only rated to about 200kg load capacity. A car seatbelt tongue is rated to hold 4000lbs (approx 1815kgs) for 30 seconds.
I do not know the strength rating requirement for an aircraft seatbelt, but I would be surprised if it was little different to automotive seatbelt strength ratings.
What the OP really needs to do is install some approved tie-down brackets for load restraint, mounted in manufacturer approved areas in the aircraft frame.
I don't understand why he thinks a few hundred dollars is a steep cost to protect yourself from cargo getting airborne and hitting you, in the event of rough flying conditions - or even worse, a sudden stop in the event of an emergency.
Grade 2 and Grade 3 are commonly known as "mild steel" bolts and have only moderate strength, being made of simple low or medium carbon steel.
Grade 5 are commonly called "high tensile" and are made of medium carbon steel, quenched and tempered. They have a minimum tensile strength of 120,000psi.
Grade 8 fasteners are the strongest of the SAE ratings, being made of heat-treated low alloy steel and meeting a minimum of 150,000psi tensile strength.
Grade 5 fasteners can be recognised by the 3 dashes on the head of the fastener. Grade 8 fasteners are recognised by the 6 dashes on their heads.
All automotive seatbelt hardware I have ever seen (that's quite a bit) utilises Grade 8 fasteners.
Some manufacturers rate their hardware higher than Grade 8 - but this is not recognised by the SAE.
Caterpillar rate their crawler tractor track shoe bolts at Grade 9 and 180,000psi tensile strength, but this is a Caterpillar rating, not SAE.
Caterpillar quite often refuse to adopt SAE ratings and produce their own standards.
Unbrako produce alloy steel socket head (Allen head) capscrews that are rated at a consistent 190,000psi tensile strength, when the usual standard for U.S.-made socket head capscrews is 170,000-180,000psi tensile strength.
There is no SAE Grade for the high strength alloy steel capscrews.
Metric hardware is rated as Classes, not Grades. Metric Classes are Class 8.8, CLass 10.9 and Class 12.9.
These "classes" are approximately aligned in tensile strength with the SAE Grade 5, Grade 8, and Grade 9.
Aircraft AN bolts are rated at 125,000psi tensile strength, thus making them only slightly stronger than SAE Grade 5 hardware.
25mm webbing cam lock straps are only rated to about 200kg load capacity. A car seatbelt tongue is rated to hold 4000lbs (approx 1815kgs) for 30 seconds.
I do not know the strength rating requirement for an aircraft seatbelt, but I would be surprised if it was little different to automotive seatbelt strength ratings.
What the OP really needs to do is install some approved tie-down brackets for load restraint, mounted in manufacturer approved areas in the aircraft frame.
I don't understand why he thinks a few hundred dollars is a steep cost to protect yourself from cargo getting airborne and hitting you, in the event of rough flying conditions - or even worse, a sudden stop in the event of an emergency.
Last edited by onetrack; 31st May 2016 at 12:48.
Problem is that the tie down (cargo securing) requirements appear to be the same across all operations.
Ok for large aircraft, however small GA aircraft - not applicable IMHO.
Ok for large aircraft, however small GA aircraft - not applicable IMHO.
I do not know the strength rating requirement for an aircraft seatbelt, but I would be surprised if it was little different to automotive seatbelt strength ratings.
Quite different, actually, which makes the CASA ban on car seat belt material such a steaming great joke. It is quite inferior to automotive material.
Last time I looked, all that as required was to demonstrate a 1000lb load, steadily applied, no allowance for shock loading, a twisted belt or any wear or damage.
Tootle pip!!
AFAIK, anything fitted to a certified aircraft requires an STC or TSO or came with the aircraft. I'm not even sure you could legally fit the McFarlane parts without a LAME doing it (you can remove seats legally).
Hence using anything from super cheap auto leaves you open to criminal prosecution if you are ramp checked by CASA.
To put that another way, you need a Cessna certified cargo net (it's in the c172 POH) to restrain your gear backed up by certified tie down ratchets. It shouldn't cost more than your entire camping trip budget even if you can find them.
Hence using anything from super cheap auto leaves you open to criminal prosecution if you are ramp checked by CASA.
To put that another way, you need a Cessna certified cargo net (it's in the c172 POH) to restrain your gear backed up by certified tie down ratchets. It shouldn't cost more than your entire camping trip budget even if you can find them.
OneTrack
ISO 898-1. http://itc.co.ir/wp-content/uploads/...98-1_2009E.pdf
Australia (and basically the whole non-US world) adopts UN ECE regulations which do not recognise SAE standards (the one exception I am aware of is dimensions for the SAE H-point dummy).
My point about seatbelt strength has, I think, been lost.
A chain is only as strong as the weakest link. Seatbelts are attached with (I think) 7/32 AN bolts attached to typically 1.0 mm steel brackets that are often pop riveted to the aluminium fuselage without reinforcement plates. I wouldn't like to guess the strength of the attach point, but it won't be good and is certainly not designed for forward moving crash loads. I suspect the manufacturers really intended them for in flight turbulence. Use whatever webbing you want. The failure point will be the attachment.
Frankly, the same argument probably works for seat rails. The seat rails are designed to have seat loads push down on them, not pull. While the seat rail looks good and chunky, its attachment may not be very strong in tension (ie pulling from load restraint belts).
How will you secure the same gear in the car driving to the airport?? Big chance it will be unsecured on the rear seat?? Sometimes we get carried away with aircraft.
ISO 898-1. http://itc.co.ir/wp-content/uploads/...98-1_2009E.pdf
Australia (and basically the whole non-US world) adopts UN ECE regulations which do not recognise SAE standards (the one exception I am aware of is dimensions for the SAE H-point dummy).
My point about seatbelt strength has, I think, been lost.
A chain is only as strong as the weakest link. Seatbelts are attached with (I think) 7/32 AN bolts attached to typically 1.0 mm steel brackets that are often pop riveted to the aluminium fuselage without reinforcement plates. I wouldn't like to guess the strength of the attach point, but it won't be good and is certainly not designed for forward moving crash loads. I suspect the manufacturers really intended them for in flight turbulence. Use whatever webbing you want. The failure point will be the attachment.
Frankly, the same argument probably works for seat rails. The seat rails are designed to have seat loads push down on them, not pull. While the seat rail looks good and chunky, its attachment may not be very strong in tension (ie pulling from load restraint belts).
How will you secure the same gear in the car driving to the airport?? Big chance it will be unsecured on the rear seat?? Sometimes we get carried away with aircraft.
If it was me, I would chuck the gear in the back, put a cargo net over it and head off camping. Nothing to it at all. Tie the net to the seat belt anchorage points. You want the gear to stay put in turbulence and under heavy braking. Don't crash.
If you want rail tie down points for your net, get them but expect to pay.
If you want rail tie down points for your net, get them but expect to pay.
Moderator
To put that another way, you need a Cessna certified cargo net
Not quite. The aircraft design requirements are published and locally approved tie down arrangements are (used to be) the usual way to go if you don't incline to the OEM style of things.
More than a few OWTs in this thread.
Motor vehicle restraint standards far exceed those prescribed as minimum for aircraft but, looking historically, that is reasonable .. the aircraft is presumed to crash on a "reasonable" surface (without excessive hard bits to run into .. ie the planned forced landing style of event) for which the prescribed restraint requirements are reasonably appropriate .. the motor vehicle really needs to look at head-ons and single vehicle run offs into significant obstacles. Hence, for aircraft, forward restraint of 9g (12g if one wants to be compatible with the older seating standards) against something approximately equivalent to 22g. While it hasn't made it into too many lighties, the current aircraft dynamic seat standards move a long way towards motor vehicle standards ..
Note that it is not at all difficult to design hardpoints to handle 20g+ in aircraft .. one just runs a structural strap over several frames or similar .. have done that in a number of cases in the past.
Keep in mind that somewhere in the order of 25-30g is the limit for the human body (aortas tear out .. stuff like that) .. hence we see 25G military seats.
As an aside, I am shortly to do my heavy vehicle endorsement and am studying up on the story .. it appears that truck load restraint is only 0.8g ? .. that doesn't impress me much at all ..
That is not to say that we design chaps stick to the minimum prescribed requirements .. in my (previous) ANR40/CAR35 life, I always went somewhat above as the weight penalty generally wasn't severe .. and, occasionally, I knew that I was going to be in front of said load.
Indeed, after one prang involving a Type which had my freight restraint system incorporated, the senior then BASI investigator gave me a call at home to let me know that the aircraft had disintegrated around my restraint system .. comforting and helps to keep one out of court discussions ...
Not quite. The aircraft design requirements are published and locally approved tie down arrangements are (used to be) the usual way to go if you don't incline to the OEM style of things.
More than a few OWTs in this thread.
Motor vehicle restraint standards far exceed those prescribed as minimum for aircraft but, looking historically, that is reasonable .. the aircraft is presumed to crash on a "reasonable" surface (without excessive hard bits to run into .. ie the planned forced landing style of event) for which the prescribed restraint requirements are reasonably appropriate .. the motor vehicle really needs to look at head-ons and single vehicle run offs into significant obstacles. Hence, for aircraft, forward restraint of 9g (12g if one wants to be compatible with the older seating standards) against something approximately equivalent to 22g. While it hasn't made it into too many lighties, the current aircraft dynamic seat standards move a long way towards motor vehicle standards ..
Note that it is not at all difficult to design hardpoints to handle 20g+ in aircraft .. one just runs a structural strap over several frames or similar .. have done that in a number of cases in the past.
Keep in mind that somewhere in the order of 25-30g is the limit for the human body (aortas tear out .. stuff like that) .. hence we see 25G military seats.
As an aside, I am shortly to do my heavy vehicle endorsement and am studying up on the story .. it appears that truck load restraint is only 0.8g ? .. that doesn't impress me much at all ..
That is not to say that we design chaps stick to the minimum prescribed requirements .. in my (previous) ANR40/CAR35 life, I always went somewhat above as the weight penalty generally wasn't severe .. and, occasionally, I knew that I was going to be in front of said load.
Indeed, after one prang involving a Type which had my freight restraint system incorporated, the senior then BASI investigator gave me a call at home to let me know that the aircraft had disintegrated around my restraint system .. comforting and helps to keep one out of court discussions ...
Moderator
Yes.
Perhaps a true comment.
Problem is .. what might your story be after the prang when you are in the box at the coronial ? ... been there, done that .. and survived quite nicely with my conservative approach to such matters.
Of course, one can be less conservative and trust to the Fates that one doesn't end up in such circumstances .. pays your money and takes your chances ..
Perhaps a true comment.
Problem is .. what might your story be after the prang when you are in the box at the coronial ? ... been there, done that .. and survived quite nicely with my conservative approach to such matters.
Of course, one can be less conservative and trust to the Fates that one doesn't end up in such circumstances .. pays your money and takes your chances ..
Yes.
Perhaps a true comment.
Problem is .. what might your story be after the prang when you are in the box at the coronial ?
Perhaps a true comment.
Problem is .. what might your story be after the prang when you are in the box at the coronial ?
But, JT, you have pointed out the reason. In a car its highly unlikely there would be a coronial investigation. In an aircraft, its highly likely. sigh.
The original poster is asking about Cessna seat rail attachments. Sadly I included my set in the sale of my last Cessna otherwise I would loan them. Surely there is someone on this site who could lend some to rioncentu. Unless he owns the said C210, $400.00 is a bit much to tie down camping gear in someone else's aeroplane on a one off trip. Sadly there is no really good alternative.
If however, the OP owns the said C210, $400.00 is money very well spent.
If however, the OP owns the said C210, $400.00 is money very well spent.
Thread Starter
Thanks everyone. Some interesting discussion in here as usual!!
yes had found them from McFarlane however the initial enquiry showed them as unavailable from McFarlane.
Need some just behind the front row of seats as there is nothing there to tie down to. From there back, yes there are seat belt anchors and then the cargo net anchors in the rear.
Cheers
yes had found them from McFarlane however the initial enquiry showed them as unavailable from McFarlane.
Need some just behind the front row of seats as there is nothing there to tie down to. From there back, yes there are seat belt anchors and then the cargo net anchors in the rear.
Cheers
You can make these if you have a workshop, a welder and associated stuff. You get 3/4 inch thick walled square tube and cut a slit down one edge. You then drill a hole and weld a nut on the opposite side. The nut is threaded to take commonly available eye bolts. Certified? I don't think so, but I have seen commercial operators use them.
Thread Starter
Aussie Bob I like that.
Slip them over the rails at the gap where the seats install then slide up the rail? Possible rail wear associated but for a one off use, probably OK.
Cheers
Slip them over the rails at the gap where the seats install then slide up the rail? Possible rail wear associated but for a one off use, probably OK.
Cheers
Couple of points.
Is there an approved cargo loading system in the AFM with the seats removed?
Is there cargo tie-down procedures in the AFM or POH?
Is there an approved cargo loading system in the AFM with the seats removed?
Is there cargo tie-down procedures in the AFM or POH?
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Counterpoint.
Even complying with every clause, sub-clause and note in the AFM, POH, CAR and CASR - a snot nosed CASA ramp check is going to find some obscure interpretation of what is naturally an offense of strict liability and threaten to remove you licence for life.
Just use your common sense when loading, and take a mate to help you dispose of the body if necessary.
Even complying with every clause, sub-clause and note in the AFM, POH, CAR and CASR - a snot nosed CASA ramp check is going to find some obscure interpretation of what is naturally an offense of strict liability and threaten to remove you licence for life.
Just use your common sense when loading, and take a mate to help you dispose of the body if necessary.