Hello everyone. Just back from a trip (SEA-LAX-SEA) on Alaska Airlines. On the return to SEA, I noticed most of the 737-800's and -900's parked at the gate with tail stands. Honestly, I really had not noticed this until recently. Appeared they were all supported with these yellow and orange (?) stands. What are those stands made of? How do they attach to the rear of the plane? (It looked like there was a latch or something it connected to). Why is this appearing so frequently now?

Thanks!

seat1a wrote:

Why is this appearing so frequently now?

It should be SOP with double-stretched aircraft, IMO.

Little cost, for knocking out a ton of potential liability.

This is your answer to the question "why:"

https://www.youtube.com/watch?v=JLWxD0gY__A

LAX772LR wrote:

seat1a wrote:

Why is this appearing so frequently now?

It should be SOP with double-stretched aircraft, IMO.

Little cost, for knocking out a ton of potential liability.

I agree. The damage of 1 tail tipping is probably more expensive than 1 tail stand.

Tail tipping also has a nasty habit of ripping doors off if the aircraft is stood on a contact stand.

intotheair wrote:

This is your answer to the question "why:"

https://www.youtube.com/watch?v=JLWxD0gY__A

Why would that ramper walk right in between the belt loader and the cargo door opening right after the aircraft came back down? I wouldn't go anywhere near it until I knew it was secure.

Interesting. I can understand the 737-900's possibly needing a tail stand. But the -800's? I know WN has a bunch, and AA has hundreds of them. I don't think I've ever seen one of the -800's on a tail stand.

I'm fond of the guy on the baggage tractor that slows after it settles back down and you can just see him thinking to himself "did I just see this with my own eyes!'

phlsfo wrote:

intotheair wrote:

This is your answer to the question "why:"

https://www.youtube.com/watch?v=JLWxD0gY__A

Why would that ramper walk right in between the belt loader and the cargo door opening right after the aircraft came back down? I wouldn't go anywhere near it until I knew it was secure.

DL has added them to the 739 SOP also. I worked on the proof of concept test. We had to weigh the aircraft before they did the test just so the calculations would be accurate.

Many aircraft have a predetermined spot to install a tailstand. If you were to remove both engines for maintenance of most of the 737 family it is a good idea to support the tail either with a tailstand or a tail jack. The CG moves way aft without engines installed.

slvrblt wrote:

Interesting. I can understand the 737-900's possibly needing a tail stand. But the -800's? I know WN has a bunch, and AA has hundreds of them. I don't think I've ever seen one of the -800's on a tail stand.

It might be AS SOP to tail stand all 738/739s so the rampers don't accidentally forget to tail stand the 739 by mistaking it for a 738. Or maybe the OP misidentified a 739 as a 738.

UA uses them as well for their -900s. 737-900 is written on the nose just forward of the nose wheel bay to help ground personnel identify the type aircraft.

This could be a really stupid statement but if the 739 COG is so far aft - why don't they shift some of the Fuselage length to in front of the wing so the length of the plane behind the wheels is shorter. Would this not help with Rotation angle as well?

727-200's used to have that ''issue'' as well. I remember more than one 727 doing a 'tail stand' when improperly loaded/offloaded . And...if it's attached to a jetbridge, well.....bye, bye, front door.

You don't get as *many* ground strikes with a -800 but they still happen. So with Alaska, its just easier to make it standard on all. I believe AA/WN all offload the rear bin bags first, then the front. I know Alaska had some "messy" instances in SEA when they first got the -800s and would offload both bins at the same time.

Polot wrote:

It might be AS SOP to tail stand all 738/739s so the rampers don't accidentally forget to tail stand the 739 by mistaking it for a 738. Or maybe the OP misidentified a 739 as a 738.

This. It's better to make it standard for all 738/739/739ER aircraft than to just limit them to the latter two. The stand was designed by AS/UA/DL employees working in conjunction with Boeing engineers. The stand can be extended or retracted by rotating the handles around, and it includes a pair of levels to make sure it's aligned correctly. A compressed gas spring inside the pole helps keep the aircraft balanced. When fully compressed, the mechanism will prevent the tail from dropping too far. The stand weighs about 48 pounds and can be operated by one person. A rubber tip plugs into the aircraft in a designated spot where, typically, maintenance can use a jack to lift the plane.

EA CO AS wrote:

Polot wrote:

It might be AS SOP to tail stand all 738/739s so the rampers don't accidentally forget to tail stand the 739 by mistaking it for a 738. Or maybe the OP misidentified a 739 as a 738.

This. It's better to make it standard for all 738/739/739ER aircraft than to just limit them to the latter two. The stand was designed by AS/UA/DL employees working in conjunction with Boeing engineers. The stand can be extended or retracted by rotating the handles around, and it includes a pair of levels to make sure it's aligned correctly. A compressed gas spring inside the pole helps keep the aircraft balanced. When fully compressed, the mechanism will prevent the tail from dropping too far. The stand weighs about 48 pounds and can be operated by one person. A rubber tip plugs into the aircraft in a designated spot where, typically, maintenance can use a jack to lift the plane.

As I recall, isn't the ramp of the N satellite pretty sloped towards the alley (more than usual ramps)? That would probably help in making the choice to make the policy SOP (although having Menzies's irregular performance when it comes to safety also helps the case)

seat1a wrote:

Hello everyone. Just back from a trip (SEA-LAX-SEA) on Alaska Airlines. On the return to SEA, I noticed most of the 737-800's and -900's parked at the gate with tail stands. Honestly, I really had not noticed this until recently. Appeared they were all supported with these yellow and orange (?) stands. What are those stands made of? How do they attach to the rear of the plane? (It looked like there was a latch or something it connected to). Why is this appearing so frequently now?

Thanks!

For the lack of a better term, there is notch in the rear section of the aircraft where the tail stand can plug in. The ones I have seen are flexible and made out of a strong plastic or similar material. It is spring loaded so you can jam it in there and includes two levels to assist in lining it up correctly.

739s like to tail tip if too much weight is removed from the front. So, instead of having to unload the rear first on every flight, the tail stand allows you to remove people and stuff in the most economical order.

slvrblt wrote:

Interesting. I can understand the 737-900's possibly needing a tail stand. But the -800's? I know WN has a bunch, and AA has hundreds of them. I don't think I've ever seen one of the -800's on a tail stand.

Here's an -800 with a stand at DCA.

Does the tail stand travel with the aircraft or does the airline just keep one at each gate as if it was a tow bar?

kabq737 wrote:

Does the tail stand travel with the aircraft or does the airline just keep one at each gate as if it was a tow bar?

The tail stands stay with the belt loaders. At each gate, at least one belt loader will have one to be used.

The tail stand connects to a pre-existing jack point that is normally used during engine changes.

The aft-cg happens because the passengers often offload faster than they can get the bags off the jet. When the front passengers begin to deplane it has a tendancy to shift the CG Aft as all the remaining passengers are in the rear of the plane, there are still a ton of bags in the aft pits.

The procedure is to either use a delayed de-planing procedure where the passengers are not allowed to deplane until a certain amount of bags are removed from the aft cargo. Alternatively the airplane can be deplaned through the L2 door. Either of these would only be done if CG calculations indicate that the airplane was prone to tipping.

When a tailstand is used, none of these calculations or procedures are necessary.

AA ramper in SEA here. We have 737-800's only. We have never used a tail stand nor do we necessarily ever unload the rear cargo bin first as a weight and balance measure or procedure. The number of people we have available to unload the aircraft dictates whether we have the ability to unload the front and rear cargo compartment at the same time and location of gate delivery tagged items is our first priority. Long timer reader of these forums first time poster!

Related question: 727s and DC-9s had the rear stairs, which also acted as a stand. Is there a reason that concept was Is not continued with other aircraft? Is there a significant structural difference between those two aircraft and those engines on the wings that make rear stairs implausible?

Ignorant question, I know, but that's why I'm asking…

WALmsp wrote:

Related question: 727s and DC-9s had the rear stairs, which also acted as a stand. Is there a reason that concept was Is not continued with other aircraft? Is there a significant structural difference between those two aircraft and those engines on the wings that make rear stairs implausible?

Ignorant question, I know, but that's why I'm asking…

Great questions, and I look forward to getting enlightened. I'm thinking the added weight and mx caused them to disappear. Another guess that comes to mind is the increased height of the 737-100 fuselage as opposed to the DC-9/727 (due to the JT8Ds under the wings) may have been a factor.

WALmsp wrote:

Related question: 727s and DC-9s had the rear stairs, which also acted as a stand. Is there a reason that concept was Is not continued with other aircraft? Is there a significant structural difference between those two aircraft and those engines on the wings that make rear stairs implausible?

1) Rear engined planes are typically closer to the ground than underwing engined aircraft, meaning it is easier to integrate a tail stair case.
2) Those are early jets, when commercial aviation was still young and airfields lacking jetbridges or airstairs suited for jet operations was still common. Now basically every airport out there that sees commercial service has staircases they can use for basically any narrowbody and at least a few jetways. Integrated stairs comes with a weight penalty, so nobody wants them if unneeded. Hence why, for example, the 717 lacks them.

Polot wrote:

WALmsp wrote:

Related question: 727s and DC-9s had the rear stairs, which also acted as a stand. Is there a reason that concept was Is not continued with other aircraft? Is there a significant structural difference between those two aircraft and those engines on the wings that make rear stairs implausible?

1) Rear engined planes are typically closer to the ground than underwing engined aircraft, meaning it is easier to integrate a tail stair case.
2) Those are early jets, when commercial aviation was still young and airfields lacking jetbridges or airstairs suited for jet operations was still common. Now basically every airport out there that sees commercial service has staircases they can use for basically any narrowbody and at least a few jetways. Integrated stairs comes with a weight penalty, so nobody wants them if unneeded. Hence why, for example, the 717 lacks them.

No wonder 737s don't have the built-in stairs under door L1 anymore, either.

Western727 wrote:

No wonder 737s don't have the built-in stairs under door L1 anymore, either.

Ryanairs 737-800s still have them, as narrow and steep as they are FR use them on every turn-around, mobile stairs are brought to the rear. There are a few exceptions - I believe some Spanish airports ban the use of steps so airbridges are used, certainly at MAD and AGP. If the steps are out of service, for whatever reason, mobile air stars are used for the front, as well as the rear doors.

I knew there was a logical explanation!

Yep! I was working in PDX during the time we got the tail stands delivered. Every gate got one. Every plane besides the -700 and -400 got it hooked up. It was always the first thing done before any people or bags were unloaded. I don't know how many times we unloaded a -900 and had to stop because tail tip danger. It was bad. AS would try to load as much in the forward compartment but sometimes it just didn't happen. I wonder if people getting off noticed that they were walking slightly upwards to get off the plane. But now that there's tail stands it makes it easier and faster to unload and easily hit the 20 minute baggage guarantee. Great investment by AS!

WALmsp wrote:

Related question: 727s and DC-9s had the rear stairs, which also acted as a stand. Is there a reason that concept was Is not continued with other aircraft? Is there a significant structural difference between those two aircraft and those engines on the wings that make rear stairs implausible?

Ignorant question, I know, but that's why I'm asking…

The DC9 family ventral stairs were not used as tailstands. They were not designed for that purpose and could not the load of the aircraft. The 727 was rated as a tailstand. As for the 737NG I don't think the tailstand uses the the aft jack point. The jack point is a hole that a pad is inserted into. It is off center if memory is correct. The tailstand mounts at a different location on the ventral fin.

The technical term is the Tail support assembly, common in B737 Freighters to avoid a tail tipping over during loading unloading ops.
Its is not carried on the Aircraft but is present at each location the Aircraft operates too.
It screws into the Aft main Jack mounting point.

Thanks to everyone ... great information! Love to learn!