It would, I think, depend on how the squawk sheets are used. In the airline
business, each aircraft has a technical log. All the airworthiness of that
airplane is legally controlled through the tech log. All the data is backed
up with computer systems and databases, but at the end of the day, the CAA
will look to ensure the tech log is up to date if they're interested in
investigating the airworthiness status of an aircraft. The captain can make
entries of defects into the log, but only an engineer licensed by the CAA to
do so, can sign off the defect as repaired or deferred.

Someone mentioned a kind of defect (radio 2 inop) and its relevance to a
particular flight. There are essentially two types of defects. One which
grounds the airplane according to the MMEL (Manufacturer's Mininum Equipment
List). The MMEL tells the operator which systems are required as a minimum
for airworthy operations and what can be inop and still fly. The second
kind of defect is called an Acceptable Deferred Deffect, known as an ADD.
Essentially an ADD is a defect which the MMEL says can be lived with for a
set period of time. What the MMEL says is acceptable and not is based on
the design of the aircraft or system, nature of the failure of the
component, and a statistical analysis of a problem occurring based on having
that component inop for a certain time period. ADDs normally have a life of
3, 10, or 120 days, which means they have to be fixed by then or a
concession raised. Jeez, this is all starting to sound pretty complex. Let
me give you an example.

#2 hydraulic pump fails in flight (let's say it's a 747 and has 3 systems -
a guess. I don't really know). Captain writes it up in the tech log, the
engineer meets the airplane on arrival. Let's say the MMEL says that it's
acceptable for that system to be out for 3 days. If the engineer can fix it
there and then with the tools, spares, and time he has available, he'll do
so. If he can't, he'll raise the defect as an ADD and make arrangements for
it to be fixed the next day. Meanwhile, the airplane flies safely with that
hydraulic system inop. If, however, #1 hydraulic pump fails on the next
flight, the MMEL will probably say you can only dispatch with one system
inop so the airplane is now grounded until at least one of the systems is
repaired. Once the repair of either system is made, a licensed engineer
makes a note in the tech log entry that the system has been repaired and
sends the airplane on it's way.

That's how it works in the airline industry. I can only assume the flight
school squawk sheets are essentially the same as a tech log. If the
airplane has a defect (GPS inop) and it's still available for use on the
schools books, it must be an ADD with a defined life to it. If it wasn't
ADDable, the airplane would be grounded until the defect was repaired.

I hope that helps. I may have confused myself in trying to explain
something I deal with every day at work, but I think it's correct.

Now the next question is how dirty your flight school lets its airplanes
get - in other words, how many ADDs do they have on the airplanes at any one
time. Too many may still be safe but is limiting for the student (fi you
want to do VOR work and the VOR is always broken, it's still perfectly safe
for VFR flight, you just can't do the training you want to do) and it's also
indicative of a cheap and unprofessional maintenance standard - possibly an
indicator toward management's attitude about the whole business.

Shawn
"Greg Esres" wrote in message
...
I'm curious as to the legal status of the squawk sheets for airplanes
at flight schools or FBOs. There has been some discussion as to who
is "legal" to sign off on a return to service after a renter has
written a squawk. Some mechanics say instructors can do so.

My suspicion is that squawk sheets have no legal standing at all, and
any pilot can choose to fly a squawked airplane if he believes it
legal and safe to fly.

Anyone have information regarding this?