This invention generally relates to mechanical engineering field and
particularly narrates about designing of overhanging mounting structure
for installation of Avionic LRU in aircraft.
3 Background of the Invention
A structure was required to install two LRUs one over other in a confined
10 space between top fuselage skin and interior panel of the aircraft where
only one side existing aircraft structure is available.
To achieve this rigid overhanging mounting structure is designed in such a
way that it install two LRUs one over other and is attached to one of the
existing aircraft upper Frame structure on one side only.
15 4 Prior Art
US51 09643: The cited invention relates to an overhang struciure that is
particularly adaptable for use as a carport. In particular, the cited invention
relates to a structure with a uniquely constructed roof channel member
that secures the roof panels of the awning structure. The channel member
20 of the invention preferably has a horizontally oriented H shaped crosssection,
and the channel member consists of an upper plate member and
a lower plate member with mating male and female securing members
joining them together, Provision is made for electrically wiring the channel
members.
25 5 Summary of the Invention
The present invention entails an overhanging structure assembly, which is
used for installation of avionic LRUs. This type of mounting structure is
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Applicant: Hindustan Aeronautics Limited
designed to attach with existing aircraft or other platform structure where
only one side. structure is· available. The present invention provides rigid
and stiff mounting structure for installation of Avionic LRUs even in
overhang scenario.
5 6 Detail Description of the Drawings
Figure 1 is Side views of overhanging mounting structure.
Figure 2 is Isometric View of overhanging mounting structure.
7 Detail Description of the Invention
Overhanging mounting structure for installation of Avionic LRU's is used for
10 installation of LRUs for communication system of the aircraft. This
structure has been designed to install two LRUs one over other in a
confined space between top fuselage skin and interior panel of the aircraft.
This mounting structure is attached to one of the existing aircraft upper
Frame structure on one side only which makes the structure overhanging.
15 The mounting structure has been designed such that in spite of
overhanging, the structure is rigid, stiff and meetS structural strength
requirement for installation of LRUs.
The details of components are given below for the most preferred
embodiment. Overhanging mounting structure comprises of RH Bracket (1)
20 made of aluminium by machining act as primary support bracket , LH
Bracket (2) is also machined bracket made of aluminium, Bottom Support
Plate (3) made of aluminium alloy sheet attached with LH and RH Bracket
with nuts and bolts. Channel (4) is made of aluminum alloy sheet and used
to reinforce existing aircraft structure where the overhanging mounting
25 structure is attached to it. RH upper Bracket (5) made of aluminium by
machining act as primary support for upper shelf, LH upper Bracket (6) is
also machined bracket made of aluminium. Upper Support Plate·(?) made
of aluminium alloy sheet attached with LH and RH Bracket with nuts and
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Applicant: Hindustan Aeronautics Limited
bolts. Angle (8) is made up of aluminium alloy and used to bridge RH
upper Bracket (5) to RH Bracket (1) and LH upper Bracket (6) to LH
Bracket (2) to provide rigidity and structural strength to the· overhanging
structure.
5 Clear space provided on side face of RH bracket (1), LH Bracket (2), RH
upper Bracket (5) and LH upper Bracket (6) facilitates cable routing from
Antenna to LRUs installed on Bottom Support Plate (3) and Upper Support
Plate (7).
Bottom Support Plate (3) and Upper Support Plate (7) is designed in a
10 corrugated shaped sheet so that height of these items can be kept
optimum in view of limited space available between top fuselage skin and
interior panel of the aircraft. Design of Corrugated shaped sheet provide
required structural rigidity and stiffness to Bottom Support Plate (3) and
Upper Support Plate (7) which are used for mounting of LRUs over them.
15 Bottom Support Plate (3) and Upper Support Plate (7) are also provided
with lightening holes in base to allow proper heat dissipation during
operation of LRUs mounted over them. These lightening holes also reduce
weight of item (3) and item (7).
Bottom Support Plate (3) is attached to RH Bracket (1) and LH Bracket (2)
20 using plurality of fasteners Screw (14), Nut (15) and Washers (16).
Similarly Upper Support Plate (7) is attached to RH upper Bracket (5) and
LH upper Bracket (6) using plurality of fasteners Screw (14), Nut (15) and
Washers (16).
25 RH Bracket· (1). LH Bracket (2), RH upper Bracket (5) and ·LH upper
Bracket (6) is attached with aircraft existing frame structure using plurality
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Applicant: Hindustan Aeronautics Limited
of fasteners Screw (9), Anchor Nut (10) and Washers (11).
Dated this on p;'" day of Sep 2023
Signature of the Applicant
Gangadhar Tiwari, CM (Design & IPR)
for Hindustan Aeronautics Limited
Transport Aircraft Research and Design Centre, Kanpur, .India
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Applicant: Hindustan Aeronautics Limited
ANNEXURE-II
We Claim:
1. Overhanging mounting structure for installation of Avionic LRU,
comprising:
RH Bracket (1) and LH Bracket (2) which are machined angle shaped,
5 acting as primary support member;
Bottom Support Plate (3) which is made of corrugated shaped aluminium
alloy sheet for rigidity and stiffness for mounting LRU over it is
attached with RH Bracket {1) and LH Bracket (2) with plurality of
fasteners Screw {14), Nut (15) and Washers {16);
10 Channel (4) which is made of aluminium alloy sheet used to reinforce
existing aircraft structure where the overhanging mounting structure
is attached to it;
RH upper Bracket (5) and LH upper Bracket (6) made of aluminium by
machining act as primary support for upper shelf;
15 Upper Support Plate (7) which is made of corrugated shaped aluminium
alloy sheet for rigidity and stiffness for mounting LRU over it is
attached to RH. upper Bracket (5) and LH upper Bracket (6) using
plurality of fasteners Screw (14), Nut (15) and Washers (16);
Angle (8) is used to bridge RH upper Bracket (5) to RH Bracket (1) and
20 LH upper Bracket (6) to LH Bracket (2) to provide rigidity and
structural strength to the overhanging structure; and
RH Bracket (1), LH Bracket (2), RH upper Bracket (5) and LH upper
Bracket (6) is attached with aircraft existing frame structure using
plurality offasteners Screw (9), Anchor Nut (10) and Washers (11).
25 2. Bottom Support Plate·(3) and Upper Support Plate (7) as claimed in claim
1, are provided with lightening holes in base to make it lighter and to
allow proper heat dissipation during operation of LRUs mounted over
them.
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Applicant: Hindustan Aeronautics Limited
3. RH bracket (1), LH Bracket (2), RH upper Bracket (5) and LH upper
Bracket (6) as claimed .in claim 1, having clear space on their side face
facilitate cable routing from Antenna to LRUs installed on Bottom Support
Plate (3) and Upper Support Plate (7).
5 4. Bottom Support Plate (3) and Upper Support Plate (7) as claimed in claim
1, are designed in a corrugated shaped sheet so that height of these
items can be kept optimum in view of limited space available between
top fuselage skin and bottom interior panel of the aircraft.