Materials and Methods of Construction in Light Structures Page: 6 of 38
This report is part of the collection entitled: National Advisory Committee for Aeronautics Collection and was provided to Digital Library by the UNT Libraries Government Documents Department.
The following text was automatically extracted from the image on this page using optical character recognition software:
N .A.C.A. Technical Memorandum ITo. 515
feet the conditions of production and use, and then show,
by illustrations from our own factory, how the production
costs depend on suitable methods of construction and other
Wood or Motal?
I think it can now be said that this problem has been
definitely decided in favor of metal for large airplanes.
Large airplanes are still being made of wood in some coun-
tries, but probably only because the particular firms can-
not be transformed quickly enough and are not given by
their governments the opportunity to do so by the with-
drawal of orders. The English air ministry has already
announced that, after a transition period of two to throoe
years, it will place orders for only metal airplanes.
Even for small airplanes the use of metal construct
tion, in my opinion, will continually increase, but will
require more time for its development. The reason for
this lies in the fact that the construction' of 'a metal
airplane .roquir'es considerably more experimental data, as
also, due to the multiplicity of parts, more preliminary
drafting and mathematical work than a wood airplane. The
cost of such preliminary work increases relatively slowly
with the size of the airplane and thorofore represents a
smaller share of the cost of a largo airplane than of a
small one. Quantity production of small airplanes would
so reduce the ratio of the preliminary work as to render
the use of metal profitable for them also. This must be
on quite a large scale, however, for the cost of the spe-
cial apparatus for quantity production (including the ex-
pense of testing the same) must be added to the cost of
the preliminary experimentation and designing. On the
contrary, considerably more primitive and relatively
cheaper apparatus suff;ico for. the smaller number of large
airplanes. As. soon, however, as a market is found for a
large number of small metal airplanes, the wood airplane
will be a thing of the past, since in this event, it will
always. be more expensive than the corresponding metal air-
I will not enter i ito any detailed discus s ion of the
comparative weight of wood and metal airplanes. I con-
sider it settled that motal has the advantage oven in this
r.pspect, although a strict comparison can seldom be made,
Here’s what’s next.
This report can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Report.
Rohrbach, Adolf. Materials and Methods of Construction in Light Structures, report, May 1929; (https://digital.library.unt.edu/ark:/67531/metadc65364/m1/6/: accessed May 25, 2019), University of North Texas Libraries, Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.