Handling & Abuse Loads Requirements
In this post, we will learn about Handling and Abuse Loads. Even though these loads are not an FAA requirement, it is common practice to size accessible components to the abuse loading conditions. Keep reading to learn more.
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Abuse loads are ultimate loads, therefore, no need to apply any additional factors (such as a fitting factor, safety factor, casting factor etc.) in abuse load analysis/testing.
Pushing abuse loads are 300 lb from zero to 60 inches above the floor, and furthermore, they reduce linearly to 100 lb at 80 inches above floor level. See curve (1) in Figure 1 below.
In cases where it is impossible to grab with both hands, single hand pulling abuse loads are 150 lb from zero to 60 inches above the floor. Additionally, they also reduce linearly to 50 lb at 80 inches above floor level. See curve (3) in Figure 1 below.
Two hand pull abuse loads are 300 lb from zero to 60 inches above the floor. Similarly, they also reduce linearly to 100 lb at 80 inches above floor level. See curve (1) Figure 1 below.
Up abuse loads are 150 lb at floor level to 60 inches above the floor. Likewise, these loads also reduce linearly to 50 lb at 80 inches above floor level. See curve (2) in Figure 1 below.
Down abuse loads are 300 lb at floor level to 60 inches above the floor. Also, they reduce linearly to 100 lb at 80 inches above floor level. See curve (1) in Figure 1 below.
Note: Typically, a 4″x4″ area is used to apply the above loads.
Specific examples of items subject to abuse loads:
Seat or Step Loads:
For items like divan covers, cabinet tops, toilet shrouds etc. that can be used as a seat or a step, a load of 500 lb is generally required in the down direction. This load needs to be applied at the most critical area of access (inducing the largest bending moment). Also, the load is applied from the floor level up to 38 inches above floor level. Furthermore, the typical area of load application is 12″x12″ for seating, and 4″x8″ for stepping, see curve (4) in Figure 1 below.
Curtain Rail Loads:
Free span curtain rails or tracks that are accessible to grasping by hand must be designed for 200 lb down load from floor level to 84.7 inches above floor at all critical locations, curtain tracks with no free span shall be designed for a 100 lb. download at all critical locations. See curve (5) and (6) in Figure 1 below.
Galley/interior furnishing doors shall be substantiated for both open and closed door cases. For the open door case, the download as defined by curve (1) in Figure 1 below shall be applied on the top of the door at the corner opposite the hinges. For the closed door case, the two hand push/pull load as defined by curve (1) in Figure C-1 shall be applied.
Folding Trolley Loads:
Folding trolleys must be substantiated for a 300 lb abuse load or maximum placarded weight applied independently to each shelf. However, it is acceptable to distribute this 300 lb. load over the entire work surface of each shelf.
Pull-Out Table Loads:
Pull-out tables must be substantiated for a 200 lb down load applied over a 4″ x 4″ area at the most critical location, also typically applied at a corner of the fully pulled out configuration.
Bassinet Fittings Loads:
Bassinet fittings shall be substantiated for a 300 lb down and side acting abuse load applied at the most critical location on the bassinet. However, these loads are applied independently in each direction.
Ceiling Panel Loads:
Module ceiling panels shall be substantiated for a 60 lb down load simulating a person pulling on the face mask supply line. Additionally, load application shall account for a 60° cone of possible load application direction.
Magazine Rack Loads:
Based on Figure 1, the appropriate load level is applied at the most critical location, also usually at the corner.
Emergency Equipment Loads:
Based on Figure 1, the appropriate load level is applied at the most critical location and also along the most critical direction.
Assist Handle Loads:
Based on Figure 1, the appropriate load level is applied at the most critical conditions, directions and locations. In certain conditions, for instance, when used by a flight attendant for evacuation (by the door), it must meet certification requirements.
In conclusion, abuse loads may very well be the sizing load case for certain components. Therefore, ignore them at your own peril (just kidding!).
Having said that, I hope you enjoyed reading through this blog post and learnt from it. Also, please feel free to leave your comments below.
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