AOPA Turbine Pilot Magazine - August 2019 - T-16

T-16 |

to save money on fuel would result in circling until the extra 200 pounds of fuel are
burned and weight is reduced below MLW.
The last weight the pilot must consider,
maximum zero fuel weight (MZFW), can be
more of an issue for some aircraft than others. MZFW is what it sounds like-the most
the loaded aircraft is permitted to weigh if
all fuel was drained from the tanks. Or, put
another way, the weight of the empty aircraft loaded with passengers and baggage.
Excess weight in the passenger and baggage
compartment could cause wing bending and
stress on the wing attach points beyond
design limits, so the total the wings can support drives the MZFW restriction.
For some aircraft, MZFW is essentially
impossible to exceed, while for others it can
be a major loading issue. A first-generation
Embraer Phenom 100, for example, will typically have an empty weight of around 7,000
pounds, and a MZFW of 8,444 pounds. With
only six seats in the aircraft, the seats would
have to be full, with the average weight of
each passenger and their baggage exceeding
240 pounds, for the MZFW to be exceeded.
Contrast this with a Cessna Citation CJ2

with an empty weight of 7,700 pounds, and
a MZFW of 9,300 pounds. The 1,600 pounds
of maximum passenger and baggage load
must be spread among nine seats. That
means an average allowance of only 178
pounds per seat, which could easily exceed
MZFW if the airplane is full and all passengers have baggage.
Once weight restrictions are complied
with, the pilot still isn't quite out of the
woods. That's because center of gravity calculations take on extra importance in some
jets. Again, while some light jets will tolerate nearly any possible loading that complies
with weight restrictions, others can exhibit
tendencies toward one end or the other of
the CG envelope. For example, the Citation
M2 is built on the CJ1+ airframe, but changes
in avionics resulted in heavy slide-in boxes
located in the very front of the nose baggage compartment being replaced by much
lighter components in the panel itself.
The result is an aircraft that tends
toward aft CGs when flown solo by an
average-size pilot. With a 180-pound
pilot in front and full fuel tanks, the CG of
a typical M2 will sit more than two inches

behind the aft limit. To pull the CG into
the legal range the pilot will need to place
more than 100 pounds of ballast into the
nose baggage compartment. And using
ballast presents its own issues. For example, if the pilot is flying an empty airplane
to pick up several passengers for a maximum-range flight, that extra 100 pounds
of ballast deadweight (now not needed
for CG purposes) represents 100 pounds
of fuel that can't be uploaded.
The good news for pilots is that an
extensive array of apps have been created to
allow the pilot to quickly calculate weight
and balance. Gone are the days of pencil
and calculator calculations-except occasionally, during recurrent training led by a
particularly sadistic instructor-replaced by
easily adjustable on-screen sliders and check
boxes with immediate display of remaining
allowable weight before any limitations are
exceeded. Several examples of loading scenarios can be quickly compared, and the
optimal solution derived painlessly. AOPA
NEIL SINGER is a Master CFI with more than

9,500 hours in 15 years of flying.

AVIONICS FOR
WHATEVER YOU FLY.
MAKING FLYING SAFER
AND MORE EFFICIENT WITH
THE HIGHEST-QUALITY
SOLUTIONS AVAILABLE.
FMS GNSS ADS-B JETCALL
RADALT

MEMORY MANAGEMENT

FREEFLIGHTSYSTEMS.COM

http://www.FREEFLIGHTSYSTEMS.COM

AOPA Turbine Pilot Magazine - August 2019

Table of Contents for the Digital Edition of AOPA Turbine Pilot Magazine - August 2019