Maximum loading for passenger seats.
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Maximum loading for passenger seats.
I understand that passenger seats must be able to withstand a 16g dynamic loading.
Does anyone know what seat loading these tests are based on?
I am struggling to find a reference for maximum loading for passenger seats.
It seems extraordinary in an industry that lives and dies by specifications being tested and promulgated that there is apparently no max weight given for a set of seats.
In the modern era of extremely obese travellers, am I missing something?
Are seat anchors, rails and seat belts so strong that it is a moot point?
Does anyone know what seat loading these tests are based on?
I am struggling to find a reference for maximum loading for passenger seats.
It seems extraordinary in an industry that lives and dies by specifications being tested and promulgated that there is apparently no max weight given for a set of seats.
In the modern era of extremely obese travellers, am I missing something?
Are seat anchors, rails and seat belts so strong that it is a moot point?
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§ 25.562 Emergency landing dynamic conditions.
(a) The seat and restraint system in the airplane must be designed as prescribed in this section to protect each occupant during an emergency landing condition when -
(1) Proper use is made of seats, safety belts, and shoulder harnesses provided for in the design; and
(2) The occupant is exposed to loads resulting from the conditions prescribed in this section.
(b) Each seat type design approved for crew or passenger occupancy during takeoff and landing must successfully complete dynamic tests or be demonstrated by rational analysis based on dynamic tests of a similar type seat, in accordance with each of the following emergency landing conditions. The tests must be conducted with an occupant simulated by a 170-pound anthropomorphic test dummy, as defined by 49 CFR Part 572, Subpart B, or its equivalent, sitting in the normal upright position.
(1) A change in downward vertical velocity (Δ v) of not less than 35 feet per second, with the airplane's longitudinal axis canted downward 30 degrees with respect to the horizontal plane and with the wings level. Peak floor deceleration must occur in not more than 0.08 seconds after impact and must reach a minimum of 14g.
(2) A change in forward longitudinal velocity (Δ v) of not less than 44 feet per second, with the airplane's longitudinal axis horizontal and yawed 10 degrees either right or left, whichever would cause the greatest likelihood of the upper torso restraint system (where installed) moving off the occupant's shoulder, and with the wings level. Peak floor deceleration must occur in not more than 0.09 seconds after impact and must reach a minimum of 16g. Where floor rails or floor fittings are used to attach the seating devices to the test fixture, the rails or fittings must be misaligned with respect to the adjacent set of rails or fittings by at least 10 degrees vertically (i.e., out of Parallel) with one rolled 10 degrees.
(c) The following performance measures must not be exceeded during the dynamic tests conducted in accordance with paragraph (b) of this section:
(1) Where upper torso straps are used for crewmembers, tension loads in individual straps must not exceed 1,750 pounds. If dual straps are used for restraining the upper torso, the total strap tension loads must not exceed 2,000 pounds.
(2) The maximum compressive load measured between the pelvis and the lumbar column of the anthropomorphic dummy must not exceed 1,500 pounds.
(3) The upper torso restraint straps (where installed) must remain on the occupant's shoulder during the impact.
(4) The lap safety belt must remain on the occupant's pelvis during the impact.
(5) Each occupant must be protected from serious head injury under the conditions prescribed in paragraph (b) of this section. Where head contact with seats or other structure can occur, protection must be provided so that the head impact does not exceed a Head Injury Criterion (HIC) of 1,000 units. The level of HIC is defined by the equation:
Where:
t1 is the initial integration time,
t2 is the final integration time, and
a(t) is the total acceleration vs. time curve for the head strike, and where
(t) is in seconds, and (a) is in units of gravity (g).
(6) Where leg injuries may result from contact with seats or other structure, protection must be provided to prevent axially compressive loads exceeding 2,250 pounds in each femur.
(7) The seat must remain attached at all points of attachment, although the structure may have yielded.
(8) Seats must not yield under the tests specified in paragraphs (b)(1) and (b)(2) of this section to the extent they would impede rapid evacuation of the airplane occupants.
(a) The seat and restraint system in the airplane must be designed as prescribed in this section to protect each occupant during an emergency landing condition when -
(1) Proper use is made of seats, safety belts, and shoulder harnesses provided for in the design; and
(2) The occupant is exposed to loads resulting from the conditions prescribed in this section.
(b) Each seat type design approved for crew or passenger occupancy during takeoff and landing must successfully complete dynamic tests or be demonstrated by rational analysis based on dynamic tests of a similar type seat, in accordance with each of the following emergency landing conditions. The tests must be conducted with an occupant simulated by a 170-pound anthropomorphic test dummy, as defined by 49 CFR Part 572, Subpart B, or its equivalent, sitting in the normal upright position.
(1) A change in downward vertical velocity (Δ v) of not less than 35 feet per second, with the airplane's longitudinal axis canted downward 30 degrees with respect to the horizontal plane and with the wings level. Peak floor deceleration must occur in not more than 0.08 seconds after impact and must reach a minimum of 14g.
(2) A change in forward longitudinal velocity (Δ v) of not less than 44 feet per second, with the airplane's longitudinal axis horizontal and yawed 10 degrees either right or left, whichever would cause the greatest likelihood of the upper torso restraint system (where installed) moving off the occupant's shoulder, and with the wings level. Peak floor deceleration must occur in not more than 0.09 seconds after impact and must reach a minimum of 16g. Where floor rails or floor fittings are used to attach the seating devices to the test fixture, the rails or fittings must be misaligned with respect to the adjacent set of rails or fittings by at least 10 degrees vertically (i.e., out of Parallel) with one rolled 10 degrees.
(c) The following performance measures must not be exceeded during the dynamic tests conducted in accordance with paragraph (b) of this section:
(1) Where upper torso straps are used for crewmembers, tension loads in individual straps must not exceed 1,750 pounds. If dual straps are used for restraining the upper torso, the total strap tension loads must not exceed 2,000 pounds.
(2) The maximum compressive load measured between the pelvis and the lumbar column of the anthropomorphic dummy must not exceed 1,500 pounds.
(3) The upper torso restraint straps (where installed) must remain on the occupant's shoulder during the impact.
(4) The lap safety belt must remain on the occupant's pelvis during the impact.
(5) Each occupant must be protected from serious head injury under the conditions prescribed in paragraph (b) of this section. Where head contact with seats or other structure can occur, protection must be provided so that the head impact does not exceed a Head Injury Criterion (HIC) of 1,000 units. The level of HIC is defined by the equation:
Where:
t1 is the initial integration time,
t2 is the final integration time, and
a(t) is the total acceleration vs. time curve for the head strike, and where
(t) is in seconds, and (a) is in units of gravity (g).
(6) Where leg injuries may result from contact with seats or other structure, protection must be provided to prevent axially compressive loads exceeding 2,250 pounds in each femur.
(7) The seat must remain attached at all points of attachment, although the structure may have yielded.
(8) Seats must not yield under the tests specified in paragraphs (b)(1) and (b)(2) of this section to the extent they would impede rapid evacuation of the airplane occupants.
I seem to recall back in the day (Andes Crash) that all the seats ended up piled up at the front and injured or killed many. Perhaps the increased 16g loading has mitigated that somewhat?
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I think mick is after a max weight that can be put on a seat. Not the design test to meet the 14G.
I believe that the R44 has this weight published, but yes it would be interesting to know.
I expect most come done to the cargo load limits per square (x) but what is the area of the chair over the floor area? most are on tracks that do not give a surface area.
I believe that the R44 has this weight published, but yes it would be interesting to know.
I expect most come done to the cargo load limits per square (x) but what is the area of the chair over the floor area? most are on tracks that do not give a surface area.
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The 170 or 77kg is the standard weight per passenger for loading unless you actually weigh the passengers.
In Oz, there has been some discussion on categories, as on smaller aircraft, there is a larger risk of overloading..
The use of one standard passenger weight for all aircraft can result in a high probability of overloading.
7. The practice in Australia has been to use the same standard passenger weight, irrespective of the size of the aircraft. However, this practice increases the probability of overloading the aircraft as passenger capacity decreases, and vice versa.
8. For example, when a standard weight of 77 kg is used in a 12 passenger aircraft instead of actual weights, the statistical probability of overloading the aircraft is as high as 25%. This probability diminishes to 0.0014% if the same standard weight of 77 kg is used on a very large capacity aircraft, such as a 400 passenger Boeing 747.
From the FAA, the weights are different, but include clothing weights and a 16lb carryon baggage..
In Oz, there has been some discussion on categories, as on smaller aircraft, there is a larger risk of overloading..
The use of one standard passenger weight for all aircraft can result in a high probability of overloading.
7. The practice in Australia has been to use the same standard passenger weight, irrespective of the size of the aircraft. However, this practice increases the probability of overloading the aircraft as passenger capacity decreases, and vice versa.
8. For example, when a standard weight of 77 kg is used in a 12 passenger aircraft instead of actual weights, the statistical probability of overloading the aircraft is as high as 25%. This probability diminishes to 0.0014% if the same standard weight of 77 kg is used on a very large capacity aircraft, such as a 400 passenger Boeing 747.
From the FAA, the weights are different, but include clothing weights and a 16lb carryon baggage..
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So if I weigh 60 kg and my 3 fellow bench sitters weigh on average 110 kg, what is my protection level?
What is the maximum allowable seat loading for the 4 seats mounted on the 2 seat rails at 4 small points?
What is the maximum allowable seat loading for the 4 seats mounted on the 2 seat rails at 4 small points?
So if I weigh 60 kg and my 3 fellow bench sitters weigh on average 110 kg, what is my protection level?
What is the maximum allowable seat loading
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The R44 has a passenger and baggage limit of 136kg per seat.
The GA8 has several different floor loading zones, the highest is around 93kg per square foot. This figure is for freight - section 6.4 has reference to "heavy pilots" I guess heavy could be determined by seeing when W&B goes out the window at light fuel and full fuel.
http://www.capaddison.org/ga-fm-04.pdf
The GA8 has several different floor loading zones, the highest is around 93kg per square foot. This figure is for freight - section 6.4 has reference to "heavy pilots" I guess heavy could be determined by seeing when W&B goes out the window at light fuel and full fuel.
http://www.capaddison.org/ga-fm-04.pdf
Last edited by Band a Lot; 11th May 2017 at 06:01. Reason: Forgot to add link
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I used to be a design engineer for an aircraft seating manufacturer .. long time ago, now, so the memory probably is a bit hazy and the rules may well have changed a tad.
passenger seats must be able to withstand a 16g dynamic loading.
Depends on the class of aircaft. Helicopters are the highest due to the typical prang having a high vertical velocity component.
Going back a long way (DC3, for instance) the design restraint was only 6g forward. This later changed (still a static load) to 9g .. with an overload requirement for seat attachments.
Later on, motor vehicle dynamic standards were introduced which really increased the work required in testing. End result is that, for later designs, the occupant has a very high level of crash survivability.
I am struggling to find a reference for maximum loading for passenger seats.
The design loads are in the FARs and cited standards. As far as I am aware, there is no limit regarding what the operator might put in the seat, passenger wise. Generally, if freight is seat loaded, the restriction is to the 170lb/77kg seat design load.
In the modern era of extremely obese travellers, am I missing something?
Not at all .. pick a seat row with the skinny occupants and you will maximise your survivability .. presuming that the seats behind don't separate from their attachments and take you out anyway ...
Are seat anchors, rails and seat belts so strong that it is a moot point?
The current dynamic design standards provide a very high level of crash survivability for occupants. The various attachment load capabilities are included in the various design standards if you fancy searching them out.
Even the older static standards provided pretty good survivability. Probably, the main deficiency was the ability of the seat to retain anchorage security with deformation in a crash .. this was one of the main changes when the dynamic tests came in. Another, especially important in helos, was to limit the maximum spinal loads .. current helos are only able to meet that with seats incorporating vertically controlled deformation, usually with interference attachment structures which let the seat settle downwards in a controlled manner.
170 lbs or 77 kg does seem very light, but I guess that might be an average of who might be in the seat row?
Just an old line in the sand ...
I seem to recall back in the day (Andes Crash) that all the seats ended up piled up at the front and injured or killed many.
As above, the static design standards didn't look at restraint under crash deformations. Seat departure was not uncommon.
Perhaps the increased 16g loading has mitigated that somewhat?
Not so much the inertial requirement as the requirement for the restraint to work in the sled test with pre-misalignment of the seat attachment structure.
I believe that the R44 has this weight published, but yes it would be interesting to know.
Helo (current) seating is to a much higher restraint than 14g .. I'd have to look it up but something in excess of 30g comes to mind. Certainly, and especially for helos, heavier occupants will materially decrease the survivability, especially regarding spinal injuries ...
I expect most come done to the cargo load limits per square (x) but what is the area of the chair over the floor area? most are on tracks that do not give a surface area.
Anchoring seats directly to the floor went out when 6g increased to 9g. If you have a look under the floor, you will see some heavier beams to which the seats are anchored. Nothing to do with floor limits.
The 170 or 77kg is the standard weight per passenger for loading unless you actually weigh the passengers.
170lb goes back a long ways to a report on US Army personnel in North America. I have a copy tucked away somewhere but not to hand .. sometime in the 40s as I recall. Obviously, not overly pertinent to today's fatties ... (did I mention that I am finally getting around to losing some weight ?)
In Oz, there has been some discussion on categories, as on smaller aircraft, there is a larger risk of overloading..
The CAAP is based on a study by John Klingberg, when he was with CASA. His report goes back to the 80s, as I recall .. again, I have a copy but not immediately to hand. John reviewed NHMRC statistical data and came up with the results in the CAAP. For whatever reasons, which annoyed many of us, the Authority took forever and a day to implement John's results.
If you are in Canberra, John (now retired) probably would trade a coffee or two for a briefing on his study.
Main thing to take home is that there is a statistical problem with small sample numbers (ie small aircraft). Large aircraft have the statistical lumps and bumps smoothed out somewhat ...
The US studies would be similar to John's but not based on Australian population statistics as was his.
So if I weigh 60 kg and my 3 fellow bench sitters weigh on average 110 kg, what is my protection level?
Somewhat reduced ... the usual asymmetric test loading will provide some comfort ..
What is the maximum allowable seat loading for the 4 seats mounted on the 2 seat rails at 4 small points?
The standard provides a line in the sand, not an all points guarantee. Asymmetric testing will provide some comfort.
I wouldn't worry too much about the anchorages .. for current standard seats, they are pretty good. Keep in mind that the rails, themselves, are supported by comparatively massive beam structures. One consideration is that the rails need to be anchored by structural screws at minimum pitch (normally 1") to protect against local rail bending .. local deformation can then let the button out .. which is why the better anchorages don't have round buttons alone.
The only time I've seen a max load stipulated was for an EMS stretcher, and the general opinion of pilots was that was down to the crane wire strength used to lift the stretcher to the door for loading.
The stretcher design would have been addressed as a combination of berth and freight requirements. Probably a 9g plus anchorage overload requirement.
Probably not limited by the wire, I suggest, multistrand steel cable is pretty good.
The GA8 has several
The original design chief for the GA8 is a PPRuNe poster so he may be along sometime with a comment or two ..
passenger seats must be able to withstand a 16g dynamic loading.
Depends on the class of aircaft. Helicopters are the highest due to the typical prang having a high vertical velocity component.
Going back a long way (DC3, for instance) the design restraint was only 6g forward. This later changed (still a static load) to 9g .. with an overload requirement for seat attachments.
Later on, motor vehicle dynamic standards were introduced which really increased the work required in testing. End result is that, for later designs, the occupant has a very high level of crash survivability.
I am struggling to find a reference for maximum loading for passenger seats.
The design loads are in the FARs and cited standards. As far as I am aware, there is no limit regarding what the operator might put in the seat, passenger wise. Generally, if freight is seat loaded, the restriction is to the 170lb/77kg seat design load.
In the modern era of extremely obese travellers, am I missing something?
Not at all .. pick a seat row with the skinny occupants and you will maximise your survivability .. presuming that the seats behind don't separate from their attachments and take you out anyway ...
Are seat anchors, rails and seat belts so strong that it is a moot point?
The current dynamic design standards provide a very high level of crash survivability for occupants. The various attachment load capabilities are included in the various design standards if you fancy searching them out.
Even the older static standards provided pretty good survivability. Probably, the main deficiency was the ability of the seat to retain anchorage security with deformation in a crash .. this was one of the main changes when the dynamic tests came in. Another, especially important in helos, was to limit the maximum spinal loads .. current helos are only able to meet that with seats incorporating vertically controlled deformation, usually with interference attachment structures which let the seat settle downwards in a controlled manner.
170 lbs or 77 kg does seem very light, but I guess that might be an average of who might be in the seat row?
Just an old line in the sand ...
I seem to recall back in the day (Andes Crash) that all the seats ended up piled up at the front and injured or killed many.
As above, the static design standards didn't look at restraint under crash deformations. Seat departure was not uncommon.
Perhaps the increased 16g loading has mitigated that somewhat?
Not so much the inertial requirement as the requirement for the restraint to work in the sled test with pre-misalignment of the seat attachment structure.
I believe that the R44 has this weight published, but yes it would be interesting to know.
Helo (current) seating is to a much higher restraint than 14g .. I'd have to look it up but something in excess of 30g comes to mind. Certainly, and especially for helos, heavier occupants will materially decrease the survivability, especially regarding spinal injuries ...
I expect most come done to the cargo load limits per square (x) but what is the area of the chair over the floor area? most are on tracks that do not give a surface area.
Anchoring seats directly to the floor went out when 6g increased to 9g. If you have a look under the floor, you will see some heavier beams to which the seats are anchored. Nothing to do with floor limits.
The 170 or 77kg is the standard weight per passenger for loading unless you actually weigh the passengers.
170lb goes back a long ways to a report on US Army personnel in North America. I have a copy tucked away somewhere but not to hand .. sometime in the 40s as I recall. Obviously, not overly pertinent to today's fatties ... (did I mention that I am finally getting around to losing some weight ?)
In Oz, there has been some discussion on categories, as on smaller aircraft, there is a larger risk of overloading..
The CAAP is based on a study by John Klingberg, when he was with CASA. His report goes back to the 80s, as I recall .. again, I have a copy but not immediately to hand. John reviewed NHMRC statistical data and came up with the results in the CAAP. For whatever reasons, which annoyed many of us, the Authority took forever and a day to implement John's results.
If you are in Canberra, John (now retired) probably would trade a coffee or two for a briefing on his study.
Main thing to take home is that there is a statistical problem with small sample numbers (ie small aircraft). Large aircraft have the statistical lumps and bumps smoothed out somewhat ...
The US studies would be similar to John's but not based on Australian population statistics as was his.
So if I weigh 60 kg and my 3 fellow bench sitters weigh on average 110 kg, what is my protection level?
Somewhat reduced ... the usual asymmetric test loading will provide some comfort ..
What is the maximum allowable seat loading for the 4 seats mounted on the 2 seat rails at 4 small points?
The standard provides a line in the sand, not an all points guarantee. Asymmetric testing will provide some comfort.
I wouldn't worry too much about the anchorages .. for current standard seats, they are pretty good. Keep in mind that the rails, themselves, are supported by comparatively massive beam structures. One consideration is that the rails need to be anchored by structural screws at minimum pitch (normally 1") to protect against local rail bending .. local deformation can then let the button out .. which is why the better anchorages don't have round buttons alone.
The only time I've seen a max load stipulated was for an EMS stretcher, and the general opinion of pilots was that was down to the crane wire strength used to lift the stretcher to the door for loading.
The stretcher design would have been addressed as a combination of berth and freight requirements. Probably a 9g plus anchorage overload requirement.
Probably not limited by the wire, I suggest, multistrand steel cable is pretty good.
The GA8 has several
The original design chief for the GA8 is a PPRuNe poster so he may be along sometime with a comment or two ..
Thanks for your insight JT.
Because the crane is part of the aircraft structure I suspect it may have fallen under some aviation requirement. Depending on the helo winch model, wires were limited to between 300 and 600 pounds. Thought the crane may have been subject to the same analysis of load limiting, any patient wouldn't be impressed being dropped due to wire failure from the door onto the tarmac.
A bit about wires.
http://zephyrintl.com/wp-content/upl...0-27_FINAL.pdf
Advice is to fly a Bell 205, pilot seat was placarded for a minimum of 170 pounds up front - CoG related, and the inability to control pitch up in the event of an engine failure.
Probably not limited by the wire
A bit about wires.
http://zephyrintl.com/wp-content/upl...0-27_FINAL.pdf
Advice is to fly a Bell 205, pilot seat was placarded for a minimum of 170 pounds up front - CoG related, and the inability to control pitch up in the event of an engine failure.
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pilot seat was placarded for a minimum of 170 pounds up front
bottom line, different criteria discussed here.
170lbs is the weight for regulatory compliance such as seat testing.
The GA8 has several different floor loading zones, the highest is around 93kg per square foot. This figure is for freight
other weights apply for the airline to use for loading purposes.
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A bit about wires.
Thanks for that link, Brian .. I'll go through it in detail at my leisure ... definitely likely to learn a thing or two, I'd warrant.
Quite different operational environments .. loading is static on the ground, winch is dynamic with variable loading. The former doesn't need an overly high RF .. (for me, at least) I'd be designing the winch installation for a rather more comfortable RF .. just in case I might find myself on the end of the line for some strange reason.
Advice is to fly a Bell 205, pilot seat was placarded for a minimum of 170 pounds up front - CoG related, and the inability to control pitch up in the event of an engine failure.
Quite often, when we run up a "load rules" style of loading system, we will specify minimum and/or maximum seat and baggage limits to keep the aircraft within the envelope. Long time since I looked at a 205 but I presume that the cyclic limits are incorporated into the loading data.
Load rules generally are used for small aircraft but can be seen with some of the heavier .. eg the 125 family is a pussycat for loading and usually doesn't warrant anything fancier than fairly simple load rules.
minimum? bottom line, different criteria discussed here. 170lbs is the weight for regulatory compliance such as seat testing.
Quite so. The first will be an aircraft loading restriction, the latter the airworthiness design standard load.
per square foot is much different that per seat.
As in a previous post, the seat attachment has naught to do with the distributed floor loading .. the rails or hardpoints go into a substantial frame of one sort or another.
The only time one usually sees the two related is for freight floor loading if the seat is removed .. that, usually, covers the situation that the AFM doesn't give enough detail in the loading section to allow for seat attach frame strength. If one, on the other hand, were designing a freight restraint system, one might well investigate the frame restraint and use a higher capability for a specific system.
Thanks for that link, Brian .. I'll go through it in detail at my leisure ... definitely likely to learn a thing or two, I'd warrant.
Quite different operational environments .. loading is static on the ground, winch is dynamic with variable loading. The former doesn't need an overly high RF .. (for me, at least) I'd be designing the winch installation for a rather more comfortable RF .. just in case I might find myself on the end of the line for some strange reason.
Advice is to fly a Bell 205, pilot seat was placarded for a minimum of 170 pounds up front - CoG related, and the inability to control pitch up in the event of an engine failure.
Quite often, when we run up a "load rules" style of loading system, we will specify minimum and/or maximum seat and baggage limits to keep the aircraft within the envelope. Long time since I looked at a 205 but I presume that the cyclic limits are incorporated into the loading data.
Load rules generally are used for small aircraft but can be seen with some of the heavier .. eg the 125 family is a pussycat for loading and usually doesn't warrant anything fancier than fairly simple load rules.
minimum? bottom line, different criteria discussed here. 170lbs is the weight for regulatory compliance such as seat testing.
Quite so. The first will be an aircraft loading restriction, the latter the airworthiness design standard load.
per square foot is much different that per seat.
As in a previous post, the seat attachment has naught to do with the distributed floor loading .. the rails or hardpoints go into a substantial frame of one sort or another.
The only time one usually sees the two related is for freight floor loading if the seat is removed .. that, usually, covers the situation that the AFM doesn't give enough detail in the loading section to allow for seat attach frame strength. If one, on the other hand, were designing a freight restraint system, one might well investigate the frame restraint and use a higher capability for a specific system.
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.. not to my knowledge from a regulatory point of view.
I couldn't see that ever being addressed. If anything, reality may dictate increasing the seat design standard weight at some stage.
At the same time, though, increasing occupant weights, necessarily, reduce the crashworthiness of a seat and survivability of the occupant in a mishap.
I couldn't see that ever being addressed. If anything, reality may dictate increasing the seat design standard weight at some stage.
At the same time, though, increasing occupant weights, necessarily, reduce the crashworthiness of a seat and survivability of the occupant in a mishap.
Thread Starter
Thanks one and all for the pertinent inputs.
The conclusion is; if faced with being squeezed between two obese passengers we cannot argue that the seat is loaded beyond its design spec.
One could only raise the doubt with crew that the combined weight is a potential hazard.
Does anyone else find it odd that seats do not have a specified limit?
The conclusion is; if faced with being squeezed between two obese passengers we cannot argue that the seat is loaded beyond its design spec.
One could only raise the doubt with crew that the combined weight is a potential hazard.
Does anyone else find it odd that seats do not have a specified limit?
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we cannot argue that the seat is loaded beyond its design spec.
I suggest that you most certainly can so argue. Just how significant that may be in a mishap is a discussion point, though.
I suggest that you most certainly can so argue. Just how significant that may be in a mishap is a discussion point, though.
