Real-Life Communication -- Solution
Even though engineers have their own areas of expertise, they're
expected to have skills in various additional areas. Engineers call this a
"multiple priority environment." In other words, no aerospace engineer gets
to spend the whole day in the wind tunnel.
"A lot of times people
think, 'Oh, engineering -- you won't need to write or speak or that sort of
thing, but I find myself writing technical papers all the time, speaking at
conferences, or just giving presentations to members of the team," says aerospace
engineer Shane Jacobs.
It's essential to be careful with those reports.
Sometimes an important document is only one paragraph long. Sometimes it's
a technical manual that's as thick as a phonebook!
Whatever format
a document takes, the information must be accurate. Let's put it this way:
if you base your work on wrong information, your project could turn into a
disaster. Likewise, any report you prepare had better be correct, too.
Here's
the edited version of the Hyper-X article. The * indicates where corrections
have been made.
Hyper-X
Hypersonic Experimental
Research Vehicle
For the first time since the 1994 cancellation
of the National Aerospace Plane (NASP) program,* the National Aeronautic and
Space Administration* (NASA) has begun* research into hypersonic aircraft.
Hypersonic
speed is defined as being above Mach 5 (five times the speed of sound*), or
the equivalent of * 1.6 kilometers per second (5,760* kilometers per hour)
at sea level. The fastest aircraft currently in service anywhere* in the world
is the Lockheed* SR-71,* which can cruise at slightly above Mach 3. The* fastest
passenger aircraft is still the Anglo-French Concorde,* which cruises at just
over Mach 2. Previous research by NASA conducted during the 1950s* and 1960s*
culminated with the X-15 project which, with rocket propulsion, reached a
speed of Mach 6.7. That's* the highest speed ever reached by a vehicle
carrying a human passenger* (in the Earth's atmosphere).
MicroCraft,
Inc. of Tullahoma, Tennessee,* was chosen by NASA to build the Hyper-X vehicles.
*Orbital Sciences Corporation's* Launch Vehicles Division in Chandler,
Arizona,* will prepare the launch vehicles. The aircraft will be five meters
long with a wingspan* of two meters (12 feet and five feet respectively).
One
of NASA's primary goals is* to develop the technologies for air-breathing*
hypersonic flight (the X-15 being rocket* powered). The* Hyper-X program will
flight validate key propulsion and related technologies toward this aim. Heading
the list for concept demonstration is the ramjet/scramjet engine.
*Ramjets
are commonly used as power plants for guided missiles. They function only
when there is sufficient forward speed to allow compression of incoming air
within the engine inlet. To get a missile off the ground and up to a speed*
at which the ramjet can function,* booster* rockets are used. Air entering
the ramjet engine is slowed to subsonic speed and compressed by shock waves*
set up by the geometry of the engine inlet duct. Combustion of fuel then takes
place in a subsonic airstream. This can be a very efficient process at moderate
supersonic speeds.
*At hypersonic speeds, however, the air passes right
through the engine at speeds greater than Mach 1, and so combustion of fuel
in a supersonic airstream is required. Hence, the Scramjet -- Supersonic Combustion
ramjet -- was developed.
Whereas rocket-powered* craft such as the
X-15 require a source of oxygen to be carried on-board, the ramjet/scramjet
takes its* oxygen from the atmosphere, like a gas turbine. The ramjet/scramjet
craft should, therefore,* be able to carry more payload because of not having
to carry oxygen.