discussion Lancaster: Stalks and blobs; Aerial Attachment Point

[Guest]

My Revell 1/72 kit includes several tiny parts consisting of a stalk about 2 inches long (on the original) with a small streamlined blob on the end. There are two per fin-please see the attached diagramme (parts 135) and another two on the other sides of the fins (not included in the diagramme).Their orientation (hanging down) seems weird:

View attachment 62396 There are also 4 even smaller stalks with blobs (part 134), mounted further down.

Here is a clip of an image taken from that fabulous source of photos, Mission4Today showing the upper stalks and blobs:

View attachment 62394

What are they for please? I don't think they can be attachment points for the aerial wire at A, because only one attachment point is needed per fin and it has to be on the inboard side, but two are also provided for the outboard sides. Also, the stalks are attached to the rudder part which of course moves, not suitable for an aerial attachment point. Also, I have seen photos of both original and models which seem to show the attachment point being the top of the fin (B). Therefore:

1. What are the stalks and blobs for?; and

2. Are the attachment points for the aerial wire the tops of the fins? If not, where are they?

Thanks.



View attachment 63850

View attachment 63852

View attachment 176876

View attachment 176878

 

[flyjoe180]

Those are mass balances Steve. Mass balances prevent control flutter by moving a control surface centre of gravity forward of a control hinge line. A prominent example of external mass balancing can be found on the elevator of the P-38 Lightning.

 

[stona]

Joe is spot on.

As for the aerial attachment on the fins.





Cheers

Steve

 

[Guest]

An answer to an earlier query of mine about these blobs introduced me to the concept of mass balances. Thanks. Wikipedia has an interesting article on the subject. However, I would never have guessed that such tiny objects could have an effect on any part of such a big plane, especially on a moving surface and sticking out into the airstream which I would have thought would have caused flutter and vibration. When returning from a mission the groundcrew would have had to search the surface for any damage to these attachments — quite a time-consuming task. I will glue them into place as the very last item, and will need to be very careful when handling it in the future.

 

[Guest]

One of mine went missing so I resorted to copper wire right through with a blob of glue on each end, much more robust than a bit of microscopic plastic

 

[Guest]

Good idea. I will too.