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Initial prediction of guided missile weight
No full textIn the initial design stages of a guided missile it is essential
tc predict the weight as accurately as is possible, and this note is
intended to be a guide in this process.
The information has been presented in a form which is applicable
to two definite stages in the evaluation of the missile. These,
for the sake of convenience, have been called the weapon system and
project design stages, and correspond to the proc.adures of formulating
the requirements for a particular missile and the initial interpretation
of them.
The note is intended to be as complete as is possible and the
weight prediction methods suggested apply to equipment and systems as
well as to structure. In some instances the formulae quoted are
derived from published work, but much of the information is the result
of original investigation. Whilst much of this investigation has been
of an empirical nature, in some cases a theoretical approach has been
used
The PN junction as a variable reactance device for F. M. production
No full textA completely transistorized modulator has been developed
for the production of frequency modulation of a 10Mc Is
carrier. A frequency deviation of 100kc s is obtained by
a change in the modulating signal of 0.15V and very
good frequency modulation results with very little amplitude
modulation
Thermal stresses in thin cylindrical shells, stiffened by plane bulkheads, for arbitrary temperature distributions
No full textA study has been made of the thermal stresses reulting near the
joint of a cylinder and internal bulkhead due to arbitrary temperature
distributions in the configuration and to the consequent compatability
forces and moments at the joint. The method is general enough to permit
the inclusion of joint thermal resistance but certain limitations are placed
on the form of the axial temperature distribution in the cylinder.
An approximate method to determine the transient temperatures for
completely general heating programmes is also proposed
Some thoughts on slender all wing supersonic airliners
No full textThe design of slender wing, supersonic airliners has been
considered from the viewpoint of obtaining maximum space utilization,
A relationship between direct operating cost on trans-atlantic services
and space utilization has been established, which shows, as might be
expected, that the direct operating costs decrease as the utilization
factor increases.
A penalty associated with a high utility factor is a high wing
loading. This leads to the necessity of using auxiliary lift when high
utilization factors are obtained, It is shown that a propulsive engine
modified to give jet lift at landing and possibly take-off is likely to
be the best means of obtaining auxiliary lift.
The optimum cruise height is less than that corresponding to
maximum lift drag ratio because of the weight penalty associated with
providing adequate thrust.
The integrated layout is not suitable for airliners required to
carry less than a hundred passengers, but becomes extremely attractive
for a very large number of passengers In this case the central part of
the wing area should be of constant depth with a cabin of side by side
multi- bubble form.
The delta planform is not ideal for an integrated layout,
Better space utilization can be obtained using a pointed pear shaped
Planform. Approximate calculations suggest that direct operating costs
of a 120 seat airliner can be reduced by as much as 25% by using this
type of layout
Atmosphere breathing engines in astronautics
No full textThe contents of this note fall into two sections. Part I considers
the possibilities and problems involved in using ramjets as a power source
for one of the stages of a satellite launching vehicle or similar project.
In comparing such a system with rocket powered vehicles, consideration is
given to both performance and mass of the various systems. Various trajectories
are considered. This work includes a reassessment of projects that have been
suggested elsewhere.
The second part examines the possibility of using forms of ramjet in
the atmosphere of other planets. Because there is insufficient knowledge
of these atmospheres, a study has been carried out to determine the approximate
performance of a chemical ramjet in atmospheres of Methane, Ammonia, Hydrogen
and Carbon Dioxide at Mach 3. The work in Part II is original, there being
no previously reported papers on the subject known.
These studies, which are necessarily based on several simplifying
assumptions, indicate that applications for these engines may be expected
to arise in astronautics, and that this is a fruitful field for further
studies
A preliminary experimental investigation of the effect of surface catalytic efficiency on stagnation point heat transfer
No full textResults of an experimental investigation to measure the difference between the
heat transfer rate to a catalytic wall and to a non-catalytic wall are presented.
Using thin film thermometer techniques, associated with an electrical analogue,
direct measurement was made of the heat transfer rate to a chemically deposited
platinum film and a vacuum evaporated silicon monoxide film. These films were
formed near the stagnation point of a pyrex glass sphere and the experiments were
done in the College of Aeronautics shock tube. The models were designed so that
the heat transfer rates were measured under identical flow conditions.
The results obtained indicate that the heat transfer rate to the platinum film
is significantly higher than the heat transfer rate to the silicon monoxide film
The development and evaluation of an ultrasonic fatigue unit
No full textA fatigue test apparatus operating at 20 kc/s is described. The unit is based
on a standard magnetostrictive drive system as used in high energy stresswave
generators. An automatic counting device has been developed and incorporated
in the final equipment, resulting in improvements in accuracy and reproducibility
of results. Some typical results of tests on aluminium alloys are presented
Characteristics of the high temperature mechanisms of creep and recovery in graphite
No full textThe research reported in this document has been made
possible through the support and sponsorship of the U.S.
Department of the Army, through its European Research Office.
This report, not necessarily in final form, is intended only for
the internal management use of the Contractor and the 1.T.S.
Department of the Army
Characteristics of the high temperature mechanisms of creep and recovery in graphite: part 3
No full textThe research reported in this document has been made possible
through the support and sponsorship of the U.S. Department of the
Army, through its European Research Office. This report, not
necessarily in final form, is intended only for the internal
management use of the Contractor and the U.S. Department of the Army
Proposals for a basic theory of air traffic control
No full textThis note serves as an introduction to the work on Air Traffic Control
currently being carried out at The College of Aeronautics.
The basic principles of Air Traffic Control are examined and a mathematical
basis for an analysis of the current and future ATC complex is discussed.
The theory is based upon feedback control concepts using intermittent data.
Examples showing the application to en-route airway and parallel track flying
are given. These demonstrate the effect of positional data up-dating rate
upon separation minima for both subsonic and supersonic aircraft. Application
to both fixed route (Airway Control) and free-route (Area Control) are
currently being considered. A full report is to be published at a later
date