Experimental Aircraft Association - Chapter 818 - Burlington, WA
YOUR FLIGHT TEST PROGRAM
By Don Hall
Before your first flight, you are issued an airworthiness certificate
by a DAR or by the FAA. This lists your operating
requirements for your 40 hours of flight test or the 5 hours after
any major changes to your aircraft.
Paragraph 8 "During the flight test phase, no person may be
carried in this aircraft during flight test unless that person is
essential to the purpose of the flight".
What does this mean? I checked with Joe Norrisat EAA Head-
quarters. The FAA position is, in the type of aircraft we build,
there is no situation where a passenger is essential. This agrees
with what the DAR told me when he approved my homebuilt
aircraft.
Think of the consequences if you take a passenger up and an
incident occurs involving property damage, injury or death.
You could lose your airman privileges, your insurance is not
valid and your estate is in great danger. Is the risk worth it?
Think twice before you take a passenger up for any reason during
your flight test period.
(If you aren't current in or familiar with the type aircraft you
have built please consider having someone who is do the initial
flight(s). It has been suggested that your first flight be kept
simple. If you have a cockpit full of whiz bank electronics
forget them until you are comfortable in the airplane and know
its flying characteristics. Navy flight training required we do a
blindfold cockpit check to prove we knew where every gauge
and control was before we went flying. Try not to fly so that
you can encounter an emergency situation you are not capable
and prepared to handle. Ross)
An article from Aviation Week & Space Technology
Mar 25, 2009
By Mike Gamauf
Since the earliest days of aviation, pilots have been staring at gauges to
help ascertain the condition of their machines and the world around them.
Orville and Wilbur had three instruments on their first Flyer: a stopwatch,
an anemometer for measuring wind speed and a tachometer. Subsequently and
especially since the introduction of instrument flight and the development
of the standard T cluster, engineers managed to cover every available inch
of cockpit real estate with some type of instrument, button or switch.
As aircraft became more complex, large passenger and military aircraft
required a flight engineer to manage the systems and scan the dozens of
gauges and lights, thereby freeing the pilots to concentrate on aviating.
In the late 1960s and early 1970s, the military sought to de-clutter its
cockpits by using small cathode ray tubes (CRT) to replace the mechanical
gauges and combine the functions of several instruments onto a
computer-generated screen. This was the genesis of the glass cockpit -
centering initially on the Primary Flight Display (PFD).
From an aircraft systems perspective, the cockpit's traditional round
"steam" gauges provide the flight crew with constant status information.
It is up to the pilots to scan the gauges, looking for misbehaving
temperatures and pressures. However, unless an advisory threshold is
reached, causing the Master caution to illuminate, dangerous trends could go
unnoticed until too late. A NASA study completed in the 1970s determined
that pilots could be just as safe with a cockpit that provides system status
on demand, instead of having information presented continuously via dials or
tapes, and with the introduction of "glass," designers embraced that concept.
Soon, the rows of steam gauges and banks of caution lights gave way to the
Multi-Function Display (MFD). This new display was kind of a general store
of aviation data, providing a home for the weather radar, flight planning,
GPS navigation aids, enhanced ground proximity warning, TCAS II and even
control of the comm/nav radios.
From a maintainer's perspective, the all-glass cockpit is an advance, and not.
In many ways, the old electromechanical gauges were easy to maintain. If the
thing was inoperative, you replaced it. They were relatively inexpensive and
many were TSOed items, which made replacements easy to find. About the worst
things that could go wrong were discovering the replacement had a short wire
bundle and wouldn't reach the connector behind the instrument panel, or you
had to apply tiny pieces of tape to the instrument's face for advisory
ranges.
By contrast, an all-glass panel provides a seemingly infinite range of
malfunctions: entire screens going dark in flight; mode switching that has a
mind of its own; black lines; error codes and good old fashioned inoperable
- all accompanied by troubleshooting nightmares. Obtaining replacement
displays, which alone cost tens of thousands of dollars, plus the additional
electronics like symbol generators, and processors can easily deplete your
maintenance reserve budget. Keeping such systems operational and safe can be
a resource and management headache.
Most pilots have embraced the all-glass cockpit and find the improved
situational awareness tools and functionality beneficial to safe flying.
With some flight departments postponing new aircraft purchases, now may be a
good time to upgrade the cockpit to take advantage of the latest safety
technology. This task usually falls on the maintenance manager's shoulders
and there are many options from which to choose. How do you make good choices
and end up with the best possible system? We asked fellow maintenance
managers and upgrade experts to shine a light on what goes on behind the
glass.
A System of Systems
Though we tend to think that the cockpit displays are just fancy television
screens, they are much more complex than your average flat-panel TV. The CRTs
of old have been largely replaced by liquid crystal displays (LCD), which
use much less energy and have much longer service lives. Early LCDs had poor
glare characteristics and limited viewing angles, but advances in the
technology now make the LCD crystal clear. The brains of the system are in
the control/display computer that takes all of the sensor, condition and
flight information and converts that digitally through the symbol generator,
then passes the info to the display through the data bus.
The pilot's PFD contains flight and navigation information. Some systems
allow pilots to customize this screen to a certain extent, but they cannot
remove the basic information necessary for flight. Screens have grown in
size from the early five-by-five-inch displays to 10 by 13 inches, and these
can hold a lot of information. In an advisory mode, a de-clutter function
will highlight whatever is the immediate problem and revert to a cleaner
display. Several systems feature a cursor controller, which takes the form of
a handgrip, trackball or joystick and is used by the pilots to point or
scroll and adjust pages on the screens.
The newest, large-format MFDs go beyond providing flight environment and nav
data and also replace the dials and caution panels to display aircraft
mechanical and system operational data. Different OEMs have varying names
for these additional functions: Engine Indication and Crew Alerting System
(EICAS), Electronic Centralized Aircraft Monitoring (ECAM) and others.
Aircraft OEMs have different ideas on how the PFD and MFD are positioned in
the cockpit. Many aircraft are equipped with an additional MFD in the center
position to further enhance the available information.
New technology brings new and complex challenges. Computers perform complex
power checks and validation of sensor inputs and data crosschecks. If the
inputs are out of tolerance, you will get an error code. Some codes are
cleared by rebooting or recycling power, but persistent codes often indicate
trouble. Fortunately for technicians, a properly designed system will have a
logical troubleshooting manual that takes you through a set of steps to
verify system health.
Many aircraft require a laptop with cable connection to interrogate the
system. Other more complex systems allow troubleshooting through the MFD
panel in a maintenance mode. Either way, technicians need to add computer
skills to their personal toolbox.
"Software, cables and laptops have become just as essential to return
aircraft back into service as pliers, wrenches or screwdrivers," said David
Romeu, aircraft maintenance manager for a small flight department in the
Northeastern United States.
The technology leap from round dials to flat panels can pose a real test for
those of us who remember what a synchro is, but the first step begins with
the desire to learn. Romeu again: "The key to being extraordinarily good at
absorbing all of this requires an additional amount of self discipline to
routinely sit down for an hour or so and educate yourself by reading the
system manuals and guides. Just as cockpit crews no longer require the
expertise of flight engineers or navigators, an aircraft technician working
today should be able to fully understand every path of logic that gets
information from an assortment of transducers and sensors onto a cockpit
display." Sending your technicians to receive training in advanced systems
is essential for keeping the equipment running smoothly.
A word of caution about getting educated. Learning the basics about one
aircraft or avionics system may not be applicable to another. Even if the
component names may be similar, you cannot count on similar functions.
"Having attended the Challenger course that uses Collins, and the Gulfstream
course that uses Honeywell, there is very little that I learned at Collins
that would help me with Honeywell. The architecture is completely different,"
said Steve Symmes, pilot and maintenance manager for a West Palm Beach,
Fla.-based engineering company. "They achieve the same goals, but in
different ways. Even the locations of the boxes are completely different
between airplane types."
As systems have become more advanced, many components are designed so that
faults can be rectified by simply swapping computer cards in the field,
rather than having to pull the entire box. Care must be taken when ordering
and loading software to maintain compatibility and configuration control of
your aircraft. Technicians also need to understand the differences between
aircraft OEM model family types. The functions of the cards and software are
not always the same, and you must refer to troubleshooting guides and
manuals before attempting to swap cards or reload software. "There is a
strict sequence and protocol for reloading software, and if you make a
mistake, you can end up losing a day reloading the entire operating
system," Symmes said. Always take advantage of system-specific training
opportunities provided by the OEMs and other vendors.
Shopping for New Glass
When it comes to aircraft upgrades, new glass cockpits are at the top of the
list for many owners. The pilots may have an idea of what they want, but
often don't completely understand the complexity involved in installing it.
So, when considering new glass, "The first thing you need to do is identify
the features and functionality that are most important to you," said Dave
Pleskac, avionics installation sales manager at Duncan Aviation in Lincoln,
Neb. Discussing the goals of the upgrade project with your pilots will help
when you are searching for both equipment and a vendor to do the work. "What
type of functionality do you need? Are you looking for high reliability?
Also very important is how will it affect my resale value? These are the
types of questions you need to ask yourself before you select a system,"
Pleskac added.
And while it is impossible to determine exactly how a new system will impact
aircraft value, particularly in the current volatile market, you should
research trends to see how different cockpit upgrades have fared over time.
Also, part of your research should include learning details of warranty and
support programs from the avionics OEM. How long is the warranty? What type
of support is provided? Can you get a loaner box or card? How easy is it to
receive software upgrades and how do you load them?
Although there are many options when selecting displays and avionics boxes,
it is the system integration that really counts. Everything has to work
seamlessly all the time. Failing that, your pilots will be distracted with
error codes and complicated switch sequencing, which is exactly what the
glass cockpit is intended to prevent.
After you have an idea on cost and system features, you should perform a
careful inventory of your aircraft equipment. If you have previous
modifications, they may affect your new system. "One of the common pitfalls
when installing a glass cockpit is getting the digital system to interface
with the analog communication and navigation," said Jim Williams, vice
president of avionics sales at Greenville, S.C.-based Stevens Aviation.
"You need to be sure that the equipment on your airplane is compatible with
the system you select. When you ask for a quote, it is important that you
have an accurate system description so that the installer will be able to
provide an accurate estimate in both time and cost."
When selecting the installer, you need to thoroughly research the various
vendors' capabilities and quality of work. If the installer holds an
existing STC for a modification that installs on your aircraft, you should
check references to see how the job went and how the modification is holding
up. If there is no existing STC, question the time to receive approval, as
well as additional costs.
"Ask them about their experience in obtaining STCs and about their accuracy
in estimating program time and cost," said Paul Magno, president of Worldwide
Helicopter Solutions, a Phoenix-based provider of aviation technical and
service solutions. "Do they have their own engineering and installation
staff? Location is important, because you'll want to be able to visit the
facility frequently to assess progress and quality as the installation
proceeds. You should always consider an installer's reputation for quality
workmanship, because a system's performance is only as good as its
installation."
See the Future
The glass cockpit is the norm for new aircraft of all shapes and sizes. Even
light sport aircraft have glass up front. Some new capabilities such as live
NEXRAD weather, taxi guidance and text communications are based on
integration with an existing MFD. "It all adds more and more bits of
information to make flying safer," said Duncan's Pleskac. And whatever
the next big breakthrough in safety technology, it is a sure thing that it
will be displayed on an MFD.
From a maintainer's point of view, the challenge posed by glass cockpits can
be met with dedication and a willingness to learn. As a maintenance manager,
you need to provide your technicians the best possible cockpit systems
training and tools to be effective, and encourage them to learn as much about
glass cockpit technology as they can.
When it comes to upgrades, you need to talk to your pilots and develop a
clear set of expectations as to what you want the system to be and do. Set
your cost and schedule objectives, then do your homework to find the best
possible equipment and installer to get the job done right the first time.
Glass cockpit technology is here to stay, and it's up to you and your team
to ensure it stays reliable, safe and effective.