preparing for commercial oral and practical

[gatt]

Hey, all. I'm getting ready for my commercial checkride. I've read the
Jeppeson PTS et al but I'd really like to hear what kinds of things people
have experienced in the oral and practical sections recently; mainly just to
see if I could hit whatever is pitched at me.

Obviously I'm expecting the "what can you do with a commercial rating"
discussion, but the DE is new to the FBO so nobody knows what kinds of
things he might throw at us.

Anybody want to share experiences?

-c

[buttman]

On May 11, 1:45 pm, "gatt" > wrote:
> Hey, all. I'm getting ready for my commercial checkride. I've read the
> Jeppeson PTS et al but I'd really like to hear what kinds of things people
> have experienced in the oral and practical sections recently; mainly just to
> see if I could hit whatever is pitched at me.
>
> Obviously I'm expecting the "what can you do with a commercial rating"
> discussion, but the DE is new to the FBO so nobody knows what kinds of
> things he might throw at us.
>
> Anybody want to share experiences?
>
> -c

Make sure you know everything on the private oral, but in more detail.
I remember having to do a complicated W+B calculation, along with a
precise fuel burn, time to climb, takeoff distance, etc. Know the
difference between private carriage, common carriage, and holding out.
(hint: only one of the three is not allowed with just a commercial).
You'll be doing at least part of the checkride in a complex airplane,
so know how the prop governor and landing gear works.

I don't remember much if any instrument questions were asked, but he
is allowed to ask you any questions relating to a rating you already
have. So if you have an instrument rating and you have no idea what an
ILS is, he can fail you.

The practical is just like the private, except you do the commercial
maneuvers instead of the basic private ones (turns around a point, s-
turns, etc). I personally didn't do stalls (the bonanza I did it in
has very harsh stalling characteristics so he didn't have me do any),
but I did do all the commercial maneuvers, slow flight, and steep
turns. Expect one odd ball thrown in, such as a manual gear extension,
emergency descent, or a prop overspeed.

[Jim Burns[_2_]]

Google Groups Advanced search in rec.aviation* will be your friend. Some
great posts during the period when Cecil Chapman worked through his
Commercial training.

Part 119.1 know that you're not looking in part 91 for these limitations.

The intricacy's of weight and balance similar to the knowledge test
questions. Load, fly, unload, fly, refuel, load, fly unload, refuel....
what's your weight, where's your CG, what about if you have to hold, when
will you reach bingo fuel and where will your CG be then? Talk to a Bonanza
owner about CG changes with fuel burn.

Spins. Study Rich Stowell's books, charts, and videos. The best I've ever
found to explain exactly what is happening during a spin. Be able to have
an in depth discussion of spins and L/D. Use FAA vernacular directly from
the FAA handbooks. Some DE's insist that in the FAA world, there are NO
other sources of information. Sad.

Required inspections. Get your hands on the log books for your test
airplane. Research all the AD's, know the recurring and single event AD's.
Print them out, put them in a 3 ring binder. Later, when you take your CFI
oral, this will pay huge dividends and save a lot of questioning. Know what
criteria your airplane must meet in order for you to operate it both
privately and commercially. Prove, through the use of the log books, that
the airplane is current and appropriate for the checkride. What about SB's?
Does your airplane need to comply? Why or why not?

Stress, re-stress, and over-stress passenger safety!! Show your DE that
above all you will use good judgment when approached with a commercial ops
proposition.

Understand and be able to explain "holding out". It gets beat to death, but
being able to accurately and completely explain it can be tricky. Use
blatant examples, don't get lead down a path into questionable areas, when
in doubt answer with "if I had any question or reservation what so ever, I'd
defer to someone like you (DE) or the FSDO and if I couldn't I'd refuse the
job". Don't dig yourself into a hole. Remember "favors" towards others
that you benefit by, even if they only secure a relationship with the other
party can and have been considered commercial ops.

Along those lines... don't use any terms that you can not fully explain.
This is a great way to dig yourself into a deep hole. Keep your answers
straight and to the point.

What's the first thing that you do if your landing gear fails to extend?
Fly the airplane. What's the 2nd? Fly the airplane. The 3rd? Relax. The
4th.... get the checklist out. Do NOT on a commercial check ride try to do
anything from memory. The checklist is your ticket. Without it, you WILL
fail.

Talk, talk, talk. Your DE will want to see your knowledge of each maneuver.
Tell him what you and the airplane are doing. Tell him why things aren't
going like they should, tell him what you should be doing and how to do it
and how the airplane will respond. If you do these things, your maneuver
can look like hell, but you've proven your knowledge of the maneuver, which
is what he wants to see.

Systems. Know your airplane's systems inside out and upside down. Talk to
an A&P about your airplane. Read the maintenance manuals. Know how
specific failures effect each system and how to identify those failures.

Minimum equipment lists. Does your airplane have one? Probably not, but
know what you can fly without and what to do if you have inop equipment.
Make SURE everything either works, or is a non-essential item and labeled
inop before your DE discovers it!

Pre flights... what do you check, why do you check it, how do you identify a
discrepancy and how come you're not using a checklist for the preflight?
What happens when you have a larger airplane? Use a checklist. Safety.

FAA Hotbutton issues. Know what the FAA has been hounding DE's about
lately. Runway incursions? Airport Hot Spots? Land and hold short ops?

As you can see, there are many areas to study. The main thing to keep in
the front of your head is that you are asking him to approve your abilities,
knowledge, judgment and decision making on a commercial pilot level. That
means that you want him to tell you that you can work in a position that
entrusts upon you the lives of innocent passengers who have no knowledge of
you or your examiners opinion of you. Those passengers are putting their
faith in you based upon his decision. Safety must be paramount.

Good luck, have fun. The commercial checkride is usually one of the easier
rides. I'm sure you'll do fine. Please let us know how it goes!
Jim

[Robert M. Gary]

On May 11, 1:45 pm, "gatt" > wrote:
> Hey, all. I'm getting ready for my commercial checkride. I've read the
> Jeppeson PTS et al but I'd really like to hear what kinds of things people
> have experienced in the oral and practical sections recently; mainly just to
> see if I could hit whatever is pitched at me.
>
> Obviously I'm expecting the "what can you do with a commercial rating"
> discussion, but the DE is new to the FBO so nobody knows what kinds of
> things he might throw at us.
>
> Anybody want to share experiences?
>
> -c

That's always tough when you are the first student for the CFI's use
of the DE. I always require the DE go fly with me before I send
students to the DE so I can see what type of guy he is. You always
want to avoid sending your students to unknown DE's when possible, but
somtimes schedules can affect that.

First, there will be no instrument questions (other than the
limitations of a non-instrument rated commerical pilot). Expect to get
a lot of questions about the limitations of a commercial pilot
operating under part 91 (i.e. what you cannot do w/o being 135).
Expect some of those situations to get pretty complicated (i.e. you
start out on a local photography flight, the photographer asks you if
you'll drop him off at point X rather than back at the airport).

-Robert, CFII

[gatt]

"buttman" > wrote in message
oups.com...

> The practical is just like the private, except you do the commercial
> maneuvers instead of the basic private ones (turns around a point, s-
> turns, etc). I personally didn't do stalls (the bonanza I did it in
> has very harsh stalling characteristics so he didn't have me do any),
> but I did do all the commercial maneuvers, slow flight, and steep
> turns. Expect one odd ball thrown in, such as a manual gear extension,
> emergency descent, or a prop overspeed.

Perfect! Thanks.

[gatt]

"Robert M. Gary" > wrote in message
ups.com...
>
> Expect some of those situations to get pretty complicated (i.e. you
> start out on a local photography flight, the photographer asks you if
> you'll drop him off at point X rather than back at the airport).

Would answering "Not unless you have a parachute" get me in trouble? ;>

Thanks, everybody!

-c

[gatt]

Top posting for brevity: Thanks, Jim, and everybody else. This is exactly
what I was hoping for just so I don't forget about something obvious.
Have a safe and glorious weekend, all!

"Jim Burns" > wrote in message
...

[...snipped and saved. ]

[Matt Whiting]

Jim Burns wrote:

> Pre flights... what do you check, why do you check it, how do you identify a
> discrepancy and how come you're not using a checklist for the preflight?
> What happens when you have a larger airplane? Use a checklist. Safety.

This is interesting as I watch a lot of airline pilots do their
preflight and I've NEVER seen one carry a checklist. A flashlight, but
never a checklist. Personally, I like the Navy approach to checklists.
Execute the list from memory and then "check" it with the checklist.
That way in an emergency you know the procedures and can do them
instantly and come back when things are more under control and check
what you've done.

I realize the FAA doesn't agree with this, but it makes a lot more sense
to me than fumbling for a checklist when the prop is windmilling and you
are descending at 800 fpm towards hostile terrain.

Matt

[gatt]

"Matt Whiting" > wrote in message
...


> This is interesting as I watch a lot of airline pilots do their preflight
> and I've NEVER seen one carry a checklist. A flashlight, but never a
> checklist. Personally, I like the Navy approach to checklists. Execute
> the list from memory and then "check" it with the checklist.

This ought to be its own thread, esp in r.a.s. The previous DE was a
checklist fanatic so I was told that when I leveled off I better have
flipped the checklist to CRUISE and on the way back to the field, I better
have gone through the DESCENT checklist and be ready for LANDING.

I guess for pre-flight, I use the Navy approach, largely because I look for
stuff beyond what's on the checklist itself but I also glance at the list at
each position around the plane. Then, before the walkaround, I stand at the
nose, look at the airplane, check the preflight checklist one last time.

> I realize the FAA doesn't agree with this, but it makes a lot more sense
> to me than fumbling for a checklist when the prop is windmilling and you
> are descending at 800 fpm towards hostile terrain.

Yep. I try to be proficient at both but solely reliant on neither. I'm
already working on memorizing it so if he says to do something I can flip to
the page, recite it from memory and double-check. That ought to be
reasonable; otherwise, you'd have to look at the list every time you did a
GUMPS check.

-c

[Barry C]

"gatt" > wrote in
:

>
> Hey, all. I'm getting ready for my commercial checkride. I've read
> the Jeppeson PTS et al but I'd really like to hear what kinds of
> things people have experienced in the oral and practical sections
> recently; mainly just to see if I could hit whatever is pitched at me.
>
> Obviously I'm expecting the "what can you do with a commercial rating"
> discussion, but the DE is new to the FBO so nobody knows what kinds of
> things he might throw at us.
>
> Anybody want to share experiences?
>
> -c


Know how the landing gear work as well as how the propeller works. Those
were important for my checkride oral.

Good luck! I'm sure you'll do just fine.


Barry
CP-ASEL-IA
AGI
CFI-candidate
FAASTeam Representative

[Jose]

> Expect to get
> a lot of questions about the limitations of a commercial pilot
> operating under part 91 (i.e. what you cannot do w/o being 135).
> Expect some of those situations to get pretty complicated (i.e. you
> start out on a local photography flight, the photographer asks you if
> you'll drop him off at point X rather than back at the airport).

I take it the answer would be no. But what about you start out on a
local photography flight, you get diverted and have to land. As it
turns out, this is near where the photographer needs to be, so he
decides not to fly back when the reason for the diversion ends?

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
for Email, make the obvious change in the address.

[Jim Burns]

The DE will want to see that you know that checklists are important and that
you use them appropriately. Matt makes a good point, there are Do first and
verify type ops or phases, but there are also Checklist first, do second and
verify type ops or phases. The point is that when you move up into faster
and more complex airplanes you must be able to use good judgment to discern
between the two. For instance, the cruise portion of our Aztec checklist
only has a couple items with the only action items being to close the cowl
flaps and to lean, but, it mentions verifying everything that should have
been performed in the climb checklist. Most twins have specific fuel tank &
crossfeed settings for different phases of flight, if you switch between
airplanes your mind will mix them up at one point or another unless you're
in the habit of using the checklist. There will be a day when GUMPS will
have a lot more letters in it.

Jim

[buttman]

On May 11, 8:08 pm, Jose > wrote:
> > Expect to get
> > a lot of questions about the limitations of a commercial pilot
> > operating under part 91 (i.e. what you cannot do w/o being 135).
> > Expect some of those situations to get pretty complicated (i.e. you
> > start out on a local photography flight, the photographer asks you if
> > you'll drop him off at point X rather than back at the airport).
>
> I take it the answer would be no. But what about you start out on a
> local photography flight, you get diverted and have to land. As it
> turns out, this is near where the photographer needs to be, so he
> decides not to fly back when the reason for the diversion ends?
>
> Jose


My guess would be since the passenger is paying for a photography
flight, not a charter flight, it should be allowed. The only way for
it to be illegal would be if the passenger paid for the flight,
knowing he would land somewhere else. Since the diversion was
incidental, I don't think it could be considered common carriage. I
don't do that kind of flying, so I'm not totally sure.

There are 4 rules that determine whether a flight is common carriage
or not. 3 of these rules are very clear cut (people or property, from
place to place, for hire) and the last one (holding out) is really
vague. Basically if the FAA says you're holding out, you're holding
out. I believe there's an AC published (AC 120-12A)that goes into
detail what is holding out. To quote it directly, "the issue is the
nature and character of the operation".

So if the pilot was doing an honest diversion, it should be OK. If the
pilot was doing a **WINK** **WINK** "diversion", he would get in
trouble. At least thats how I see it.

[Peter Dohm]

"buttman" > wrote in message
ups.com...
> On May 11, 8:08 pm, Jose > wrote:
> > > Expect to get
> > > a lot of questions about the limitations of a commercial pilot
> > > operating under part 91 (i.e. what you cannot do w/o being 135).
> > > Expect some of those situations to get pretty complicated (i.e. you
> > > start out on a local photography flight, the photographer asks you if
> > > you'll drop him off at point X rather than back at the airport).
> >
> > I take it the answer would be no. But what about you start out on a
> > local photography flight, you get diverted and have to land. As it
> > turns out, this is near where the photographer needs to be, so he
> > decides not to fly back when the reason for the diversion ends?
> >
> > Jose
>
>
> My guess would be since the passenger is paying for a photography
> flight, not a charter flight, it should be allowed. The only way for
> it to be illegal would be if the passenger paid for the flight,
> knowing he would land somewhere else. Since the diversion was
> incidental, I don't think it could be considered common carriage. I
> don't do that kind of flying, so I'm not totally sure.
>
> There are 4 rules that determine whether a flight is common carriage
> or not. 3 of these rules are very clear cut (people or property, from
> place to place, for hire) and the last one (holding out) is really
> vague. Basically if the FAA says you're holding out, you're holding
> out. I believe there's an AC published (AC 120-12A)that goes into
> detail what is holding out. To quote it directly, "the issue is the
> nature and character of the operation".
>
> So if the pilot was doing an honest diversion, it should be OK. If the
> pilot was doing a **WINK** **WINK** "diversion", he would get in
> trouble. At least thats how I see it.
>

On this one I agree with you.

As a former student pilot, and presumably a future student pilot and then
private pilot, I have no expectation of ever having this particular
discussion with a DE. However, there are a few parallels in debates
regarding the sharing of expenses and of business vs commercial flying: and
some of those can become esoteric to the point of becoming ridiculous.

A lot could also depend upon the personality of the examiner and any recent
cases and guidance he may have received. Quite a long time ago, I was
sitting in the (then) local airport restaurant and one of those present, who
I believe was primarily a charter pilot, related a story about his oral exam
for either instrument or commercial. It was long and convoluted, if true,
and he was sent back for further study a couple of times--until he happened
to answer a question with something like "I will have to look that up."
According to the story, he then passed the exam.

Given the plausible and uncommon situation described above, plus a moment of
greater insight than I usually display, I might try to dance around the
question with something like: "Well, if I was the pilot, I would have
decided where to land based upon safety of flight and whatever services
might be needed while on the ground; and I think that it would be unwise to
attempt to force him/her back into the airplane. Can you offer any guidance
in case anything similar ever occurs?"

Peter

[K Baum]

On May 11, 4:43 pm, Matt Whiting > wrote:
> Jim Burns wrote:
> > Pre flights... what do you check, why do you check it, how do you identify a
> > discrepancy and how come you're not using a checklist for the preflight?
> > What happens when you have a larger airplane? Use a checklist. Safety.
>
> This is interesting as I watch a lot of airline pilots do their
> preflight and I've NEVER seen one carry a checklist.

Just to clarify this Matt, airline pilots do not use a checklist on a
walk around because they are not required to. You can rest assured
that for evry operation that requires a checklist, it is being used.

> Personally, I like the Navy approach to checklists.
> Execute the list from memory and then "check" it with the checklist.
> That way in an emergency you know the procedures and can do them
> instantly and come back when things are more under control and check
> what you've done.

Actually, everyone (except maybe GA pilots) does things this way. In
other words, the checklist is not treated as a "To Do" list. To
elaborate further, in an emergency, there are certain "recall Items"
or "Memory Items" that you do from memory, and then procede with the
rest of the checklist. I think your observation here is very
prudent.
>
> I realize the FAA doesn't agree with this, but it makes a lot more sense
> to me than fumbling for a checklist when the prop is windmilling and you
> are descending at 800 fpm towards hostile terrain.

You hit this nail on the head! I think there are a few to many DARs
who like to express their opinions as facts when it comes to
checklists. Best thing to do is ask up front what the guy likes to
see.


>
> Matt

[Mark T. Dame]

Jim Burns wrote:
>
> The intricacy's of weight and balance similar to the knowledge test
> questions. Load, fly, unload, fly, refuel, load, fly unload, refuel....
> what's your weight, where's your CG, what about if you have to hold, when
> will you reach bingo fuel and where will your CG be then? Talk to a Bonanza
> owner about CG changes with fuel burn.

Additionally, your CG probably changes when you retract your gear.
That's one of my commercial DE's pet points.


> Use
> blatant examples, don't get lead down a path into questionable areas, when
> in doubt answer with "if I had any question or reservation what so ever, I'd
> defer to someone like you (DE) or the FSDO and if I couldn't I'd refuse the
> job".

Answering with that also tells the DE that you know that you don't know
everything and that the FAA is here to help. (-:


> Along those lines... don't use any terms that you can not fully explain.
> This is a great way to dig yourself into a deep hole. Keep your answers
> straight and to the point.

It's like going to court: they can cross examine you on any point you
bring up.


> What's the first thing that you do if your landing gear fails to extend?
> Fly the airplane. What's the 2nd? Fly the airplane. The 3rd? Relax. The
> 4th.... get the checklist out. Do NOT on a commercial check ride try to do
> anything from memory. The checklist is your ticket. Without it, you WILL
> fail.

That is true, however, my DE pointed out (and continues to point out,
since I'm flying with her for my CFI ticket) that checklists are there
to make sure you don't forget anything, they aren't "TO DO" lists. The
point is that you don't need to use the checklist to perform every task,
but make sure you at least pull it out and go through the list out loud
to verify that you have completed all items. Use common sense here: go
by the checklist for your preflight, starting, and run up. Pre-read it
for takeoff. Use it to confirm you did everything for emergency procedures.


> Talk, talk, talk. Your DE will want to see your knowledge of each maneuver.
> Tell him what you and the airplane are doing. Tell him why things aren't
> going like they should, tell him what you should be doing and how to do it
> and how the airplane will respond. If you do these things, your maneuver
> can look like hell, but you've proven your knowledge of the maneuver, which
> is what he wants to see.

I second that. If you screw up a maneuver and don't say anything,
you're more likely to fail than if you explain it as you are doing it
and then explain your mistake(s). It's not a get out of jail free card,
but being silent on a mistake is much more likely to result in a failure
than owning up to and explaining the hows and whys.

The one thing that I would recommend to know inside and out and upside
down is the privileges and limitations of the commercial certificate.
There are too many people who think that a commercial certificate give
you the right to charge for your flying. With a few specific
exceptions, it really only gives you the right to be hired by a
commercial operation. (This isn't intended to get into a long
discussion on the privileges and limitations of the commercial
certificate, only pointing out that it's a good idea to know 61.133 and
119.1.) This may not be the most important thing, but my DE felt that
it was an FAA emphasis point when I took my commercial checkride a few
months ago, so I would expect other DE's to feel the same.


-m
--
## Mark T. Dame >
## CP-ASEL, AGI
## <insert tail number here>
## KHAO, KISZ
"Making files is easy under the UNIX operating system. Therefore,
users tend to create numerous files using large amounts of file
space. It has been said that the only standard thing about all
UNIX systems is the message-of-the-day telling users to clean up
their files."
-- System V.2 administrator's guide

[Mark T. Dame]

gatt wrote:
> "Robert M. Gary" > wrote in message
> ups.com...
>> Expect some of those situations to get pretty complicated (i.e. you
>> start out on a local photography flight, the photographer asks you if
>> you'll drop him off at point X rather than back at the airport).
>
> Would answering "Not unless you have a parachute" get me in trouble? ;>

That's how I would answer it (assuming the DE has a good sense of
humor). In fact, I think I did answer it that way with regard to sight
seeing flights.


-m
--
## Mark T. Dame >
## CP-ASEL, AGI
## <insert tail number here>
## KHAO, KISZ
"Change is inevitable, except from a vending machine."

[Jose]

> Additionally, your CG probably changes when you retract your gear. That's one of my commercial DE's pet points.

Do you mean the actual CG (from the repositioning of the gear further
back, such as in a C172RG) or the change in flight behavior due to the
change in CP from removing the gear from the slipstream (such as in an
Arrow, where the gear retracts straight up)?

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
for Email, make the obvious change in the address.

[Mark T. Dame]

Jose wrote:
>> Additionally, your CG probably changes when you retract your gear.
>> That's one of my commercial DE's pet points.
>
> Do you mean the actual CG (from the repositioning of the gear further
> back, such as in a C172RG)

The actual CG. I would think that most retracts would change CG since
at least the nose gear is in a different position relative to the datum,
but I can only speak for the Arrow that I flew for my checkride.


> or the change in flight behavior due to the
> change in CP from removing the gear from the slipstream (such as in an
> Arrow, where the gear retracts straight up)?

Only the mains. The nose gear moves back.


-m
--
## Mark T. Dame >
## CP-ASEL, AGI
## <insert tail number here>
## KHAO, KISZ
"Every time you lose you die a little bit. You die inside, a portion of
you. Not all of your organs, maybe just your liver."
-- George Allen

[Jose]

> The actual CG. I would think that most retracts would change CG since at least the nose gear is in a different position relative to the datum, but I can only speak for the Arrow that I flew for my checkride.

Interesting - never thought much about it. Looking at the Arrow manual,
I see "moment due to retraction of landing gear" 819 in-lbs". Dividing
by 2000 lbs gives a CG change of about a half an inch.

Thanks.

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
for Email, make the obvious change in the address.

[Mortimer Schnerd, RN[_2_]]

Mark T. Dame wrote:
>> The intricacy's of weight and balance similar to the knowledge test
>> questions. Load, fly, unload, fly, refuel, load, fly unload, refuel....
>> what's your weight, where's your CG, what about if you have to hold, when
>> will you reach bingo fuel and where will your CG be then? Talk to a Bonanza
>> owner about CG changes with fuel burn.
>
> Additionally, your CG probably changes when you retract your gear.
> That's one of my commercial DE's pet points.


While being technically correct (if he says so), what difference does it make?
Are you going to fly with the gear down to keep the CG in the same place that
you used to figure your W&B?

Cocktail party facts....



--
Mortimer Schnerd, RN
mschnerdatcarolina.rr.com

[Jose]

> While being technically correct (if he says so), what difference does it make?

Half an inch in an Arrow.

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
for Email, make the obvious change in the address.

[Mark Hansen]

On 05/14/07 14:03, Mortimer Schnerd, RN wrote:
> Mark T. Dame wrote:
>>> The intricacy's of weight and balance similar to the knowledge test
>>> questions. Load, fly, unload, fly, refuel, load, fly unload, refuel....
>>> what's your weight, where's your CG, what about if you have to hold, when
>>> will you reach bingo fuel and where will your CG be then? Talk to a Bonanza
>>> owner about CG changes with fuel burn.
>>
>> Additionally, your CG probably changes when you retract your gear.
>> That's one of my commercial DE's pet points.
>
>
> While being technically correct (if he says so), what difference does it make?
> Are you going to fly with the gear down to keep the CG in the same place that
> you used to figure your W&B?
>
> Cocktail party facts....
>
>
>

I'm sure it was more a matter of making sure the pilot understood how the
gear affected the CG - and not that it would change the flight characteristics
all that much.


--
Mark Hansen, PP-ASEL, Instrument Airplane, USUA Ultralight Pilot
Cal Aggie Flying Farmers
Sacramento, CA

[Matt Whiting]

Mortimer Schnerd, RN wrote:
> Mark T. Dame wrote:
>>> The intricacy's of weight and balance similar to the knowledge test
>>> questions. Load, fly, unload, fly, refuel, load, fly unload, refuel....
>>> what's your weight, where's your CG, what about if you have to hold, when
>>> will you reach bingo fuel and where will your CG be then? Talk to a Bonanza
>>> owner about CG changes with fuel burn.
>> Additionally, your CG probably changes when you retract your gear.
>> That's one of my commercial DE's pet points.
>
>
> While being technically correct (if he says so), what difference does it make?
> Are you going to fly with the gear down to keep the CG in the same place that
> you used to figure your W&B?

You calculate balance for both gear down and gear up for both takeoff
and landing loading. All four must be within the envelope or you don't go.

Matt

[Mortimer Schnerd, RN[_2_]]

Matt Whiting wrote:
>> While being technically correct (if he says so), what difference does it
>> make? Are you going to fly with the gear down to keep the CG in the same
>> place that you used to figure your W&B?
>
> You calculate balance for both gear down and gear up for both takeoff
> and landing loading. All four must be within the envelope or you don't go.



Really? In the C-210 if I couldn't get the doors closed we wouldn't go, but I
don't recall any other occasions. <G>

Seriously, I've never been required to do more than one W&B for any flight I've
ever made, and I don't recall that the gear position was ever even considered.
I've never failed a written test or check ride either, including regular part
135 rides.



--
Mortimer Schnerd, RN
mschnerdatcarolina.rr.com

[Matt Whiting]

Mortimer Schnerd, RN wrote:
> Matt Whiting wrote:
>>> While being technically correct (if he says so), what difference does it
>>> make? Are you going to fly with the gear down to keep the CG in the same
>>> place that you used to figure your W&B?
>> You calculate balance for both gear down and gear up for both takeoff
>> and landing loading. All four must be within the envelope or you don't go.
>
>
>
> Really? In the C-210 if I couldn't get the doors closed we wouldn't go, but I
> don't recall any other occasions. <G>

Really.


> Seriously, I've never been required to do more than one W&B for any flight I've
> ever made, and I don't recall that the gear position was ever even considered.
> I've never failed a written test or check ride either, including regular part
> 135 rides.

Some instructors and examiners are more thorough than others. Not all
will test for everything, but checking to see that the W&B aren't
exceeded during all phases of flight is a pretty basic check.

Matt

[Mark T. Dame]

Mortimer Schnerd, RN wrote:
> Mark T. Dame wrote:
>>> The intricacy's of weight and balance similar to the knowledge test
>>> questions. Load, fly, unload, fly, refuel, load, fly unload, refuel....
>>> what's your weight, where's your CG, what about if you have to hold, when
>>> will you reach bingo fuel and where will your CG be then? Talk to a Bonanza
>>> owner about CG changes with fuel burn.
>> Additionally, your CG probably changes when you retract your gear.
>> That's one of my commercial DE's pet points.
>
>
> While being technically correct (if he says so), what difference does it make?
> Are you going to fly with the gear down to keep the CG in the same place that
> you used to figure your W&B?
>
> Cocktail party facts....

Not at all. We're talking about a commercial pilot checkride. As such,
you need to know more than for a private certificate. The point of the
exercise is to show the examiner that you understand these concepts and
actually do it.

Additionally, you do have the gear in both positions in flight. You
have it down at take off. You need to make sure that putting it up
isn't going to put your CG outside of the envelope right after take off
when you are still low, slow, and nose high. This could lead to a
departure stall. When you are landing, you put your gear down well
before you touch down, and you will be low and slow on final. The
difference between gear up and down may be a factor.

Now, as Jose pointed out, on the Arrow it's not very significant, but
that doesn't mean that it's that way for all planes.

Finally, as I said, we're talking about a checkride. Checkrides often
have you do things that you may not do in your day to day flying, but
you need to know and understand in case you need it. In any case, I'm
just giving advice on what to expect on the checkride.


-m
--
## Mark T. Dame >
## CP-ASEL, AGI
## <insert tail number here>
## KHAO, KISZ
"Love is a snowmobile racing across the tundra and then
suddenly it flips over, pinning you underneath. At night,
the ice weasels come."
-- Matt Groening

[Mark T. Dame]

Mortimer Schnerd, RN wrote:
>
> Seriously, I've never been required to do more than one W&B for any flight I've
> ever made, and I don't recall that the gear position was ever even considered.
> I've never failed a written test or check ride either, including regular part
> 135 rides.

For both my private and commercial rides I was required to do a W&B for
takeoff and landing fuel loads. Additionally, for my commercial ride, I
had to account for the gear position, as Matt said, giving you four
different configurations.

This was another point of emphasis for my DE. Different examiners have
different favorite topics. For the purpose of the original question, my
suggestion stands.

I'm not questioning your experience, just relaying mine.


-m
--
## Mark T. Dame >
## CP-ASEL, AGI
## <insert tail number here>
## KHAO, KISZ
"Small software companies are always cool."
-- Bill Gates

[Jose]

> Now, as Jose pointed out, on the Arrow it's not very significant

Actually I wasn't implying (half an inch) that it wasn't very
significant - when the CG range is only a handful of inches, it's
significant. And certainly when you're near the edge it bears watching.

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
for Email, make the obvious change in the address.

[Mark T. Dame]

Jose wrote:
>> Now, as Jose pointed out, on the Arrow it's not very significant
>
> Actually I wasn't implying (half an inch) that it wasn't very
> significant - when the CG range is only a handful of inches, it's
> significant. And certainly when you're near the edge it bears watching.

At the risk of arguing semantics, I wasn't saying "insignificant" only
"not very significant". I don't have my Arrow book here, but I believe
the CG range is around 10 to 12 inches. If you load well within the
envelope, the half inch is not going to have an appreciable affect on
aircraft performance.

But I'm getting off topic: what should someone expect on their
commercial checkride.

Make sure to do a W&B for gear up and gear down with takeoff fuel and
landing fuel. If the examiner doesn't care, then no big deal, but if
the examiner wants to see it and you didn't do it, then you have a
strike against you. On checkrides, you'll get plenty of strikes without
creating ones that could be easily avoided by a little bit of prep work.

Even if the examiner doesn't want or expect it, it can't hurt to have it
(unless you do it wrong).


-m
--
## Mark T. Dame >
## CP-ASEL, AGI
## <insert tail number here>
## KHAO, KISZ
"The way to make a small fortune in the commodities market is to
start with a large fortune."
-- Unknown

[Mortimer Schnerd, RN[_2_]]

Mark T. Dame wrote:
> For both my private and commercial rides I was required to do a W&B for
> takeoff and landing fuel loads. Additionally, for my commercial ride, I
> had to account for the gear position, as Matt said, giving you four
> different configurations.
>
> This was another point of emphasis for my DE. Different examiners have
> different favorite topics. For the purpose of the original question, my
> suggestion stands.
>
> I'm not questioning your experience, just relaying mine.


My private and instrument rides were with a retired USAF type popularly locally
known as Colonel Goddammit. I also did some of my single and multi 135
checkrides with him. He had his quirks to be sure and God help you if you
attracted his attention. First his fingers would start tapping his legs, faster
and faster until finally the blast would come, blistering the side of your face.
You'd be deaf in one ear and your hair would look like you'd been riding a
motorcycle... sideways. Sometimes I'd **** up intentionally just to get it over
with.

My commercial checkride was with a more mellow character who was a DE, former
chief pilot for a commuter, and current chief pilot for a high priced charter
outfit.

Multiengine checkride was with a similar type associated with one of those
weekend multi schools.

Later 135 rides were with an airline captain who owned a courier service on the
side and with a longtime freight dog chief pilot.

I never had to do W&B in more than one configuration my entire flying career.
Frankly, until I read the OP's note a couple of days ago, I'd never heard of
this being done. Now it's my turn to say: I'm not doubting your experience;
it's just very different from mine. Could it be this is one of those quirks
courtesy of somebody at your local FSDO who focuses on this as a way to trip
people up?



--
Mortimer Schnerd, RN
mschnerdatcarolina.rr.com

[Newps]

Mark T. Dame wrote:

>
> Additionally, you do have the gear in both positions in flight. You
> have it down at take off. You need to make sure that putting it up
> isn't going to put your CG outside of the envelope right after take off
> when you are still low, slow, and nose high. This could lead to a
> departure stall. When you are landing, you put your gear down well
> before you touch down, and you will be low and slow on final. The
> difference between gear up and down may be a factor.

Bull****. Somebody mentioned that the gear will make a 1/2" difference
in CG. I personally don't believe that, it's way too much. But
assuming it's true no airplane falls out of the sky by going from the CG
on the aft limit to 1/2" past the aft limit.

[Mark T. Dame]

Mortimer Schnerd, RN wrote:
>
> My private and instrument rides were with a retired USAF type popularly locally
> known as Colonel Goddammit.

Talk about unneeded pressure on a checkride...


> I never had to do W&B in more than one configuration my entire flying career.
> Frankly, until I read the OP's note a couple of days ago, I'd never heard of
> this being done.

Which just goes to show, even though we all fly by the same regulations,
things are not always the same. You can see those differences even from
FBO to FBO in the same area.


> Could it be this is one of those quirks
> courtesy of somebody at your local FSDO who focuses on this as a way to trip
> people up?

Possibly, but I would put my money on the DE. She has her own ideas
about what's important and what's not. She also tends to be pretty
thorough, but like most DE's she has her favorite things. My CFI (who
had done his commercial checkride with her a couple of years earlier)
gave me a list of things that I absolutely had to have ready. I don't
recall the entire list, but the W&B with both gear configurations was
one of them.


-m
--
## Mark T. Dame >
## CP-ASEL, AGI
## <insert tail number here>
## KHAO, KISZ
"There is a theory which states that if ever anyone discovers
exactly what the Universe is for and why it is here, it will
instantly disappear and be replaced by something even more bizarre
and inexplicable.

There is another which states that this has already happened."
-- The Restaurant at the End of the Universe, Douglas Adams

[Mark T. Dame]

Newps wrote:
>
>
> Bull****. Somebody mentioned that the gear will make a 1/2" difference
> in CG. I personally don't believe that, it's way too much.

You don't have to believe it. If it's in the book, that's what you use.
It's not a matter of opinion. It is what it is.


> But
> assuming it's true no airplane falls out of the sky by going from the CG
> on the aft limit to 1/2" past the aft limit.

No it doesn't. It affects the stability, the stall speed, and the
ability to recover from a stall. In an Arrow, I don't think it will
matter a hill of beans, but in a Cutlass, it might.

But the point of the conversation is preparing for the commercial
checkride, not whether or not raising the gear on a specific model of
airplane will move the CG too far aft for safe operation.


-m
--
## Mark T. Dame >
## CP-ASEL, AGI
## <insert tail number here>
## KHAO, KISZ
"Help stamp out and abolish redundancy!"

[Jose]

> Somebody mentioned that the gear will make a 1/2" difference in CG. I personally don't believe that, it's way too much.

I showed the calculation. It's in the Arrow book.

> But assuming it's true no airplane falls out of the sky by going from the CG on the aft limit to 1/2" past the aft limit.

No, but with thinking like that, if you decided to fly an inch out of CG
and ended up an inch and a half...

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
for Email, make the obvious change in the address.

[Jim Burns[_2_]]

Most of the DE's that I've encountered have a certain amount of "teacher" in
them that is very often only slightly contained. I feel that the DE's who
ask about CG changes with gear movement are trying to teach more than
torture a student the fact that you don't necessarily have to move people,
baggage, cargo, or fuel to have a CG change. Sometimes, depending on the
airplane ( and you are preparing to fly bigger and more complex airplanes)
an aircraft's CG will change due to a normal flight operation, such as
extending or retracting the gear.

I don't think the magnitude of the CG change that is the emphasis of the
DE's questions or teachings, rather the fact that it can change. I think
this lesson is meant to point out the importance of a complete understanding
of W&B as applied to each particular aircraft using the proper W&B and POH
information.

Jim

[Matt Whiting]

Mortimer Schnerd, RN wrote:
> Mark T. Dame wrote:
>> For both my private and commercial rides I was required to do a W&B for
>> takeoff and landing fuel loads. Additionally, for my commercial ride, I
>> had to account for the gear position, as Matt said, giving you four
>> different configurations.
>>
>> This was another point of emphasis for my DE. Different examiners have
>> different favorite topics. For the purpose of the original question, my
>> suggestion stands.
>>
>> I'm not questioning your experience, just relaying mine.
>
>
> My private and instrument rides were with a retired USAF type popularly locally
> known as Colonel Goddammit. I also did some of my single and multi 135
> checkrides with him. He had his quirks to be sure and God help you if you
> attracted his attention. First his fingers would start tapping his legs, faster
> and faster until finally the blast would come, blistering the side of your face.
> You'd be deaf in one ear and your hair would look like you'd been riding a
> motorcycle... sideways. Sometimes I'd **** up intentionally just to get it over
> with.
>
> My commercial checkride was with a more mellow character who was a DE, former
> chief pilot for a commuter, and current chief pilot for a high priced charter
> outfit.
>
> Multiengine checkride was with a similar type associated with one of those
> weekend multi schools.
>
> Later 135 rides were with an airline captain who owned a courier service on the
> side and with a longtime freight dog chief pilot.
>
> I never had to do W&B in more than one configuration my entire flying career.
> Frankly, until I read the OP's note a couple of days ago, I'd never heard of
> this being done. Now it's my turn to say: I'm not doubting your experience;
> it's just very different from mine. Could it be this is one of those quirks
> courtesy of somebody at your local FSDO who focuses on this as a way to trip
> people up?

I think it is just different DEs checking different things. To me W&B
is one of the things you don't skip as discretionary. Much of the stuff
covered on a check ride is stuff that won't kill you if you don't know
all of the details. Things like what every stinkin antenna on the
airplane is for. I can count on zero fingers the number of times in 30
years of flying that I had to know that to save my life. OTOH, if you
take off at the aft CG limit and retracting the gear puts you 1/2" or so
past the aft limit, this has the potential to kill you. Same with fuel
burn. If you have an airplane that shifts CG aft with fuel burn, this
can cook your goose later in the flight.

Violating rules of the FAA is one thing, but trying to violate the rules
of physics is quite another.

Matt

[Matt Whiting]

Mark T. Dame wrote:
> Jose wrote:
>>> Now, as Jose pointed out, on the Arrow it's not very significant
>>
>> Actually I wasn't implying (half an inch) that it wasn't very
>> significant - when the CG range is only a handful of inches, it's
>> significant. And certainly when you're near the edge it bears watching.
>
> At the risk of arguing semantics, I wasn't saying "insignificant" only
> "not very significant". I don't have my Arrow book here, but I believe
> the CG range is around 10 to 12 inches. If you load well within the
> envelope, the half inch is not going to have an appreciable affect on
> aircraft performance.
>
> But I'm getting off topic: what should someone expect on their
> commercial checkride.
>
> Make sure to do a W&B for gear up and gear down with takeoff fuel and
> landing fuel. If the examiner doesn't care, then no big deal, but if
> the examiner wants to see it and you didn't do it, then you have a
> strike against you. On checkrides, you'll get plenty of strikes without
> creating ones that could be easily avoided by a little bit of prep work.
>
> Even if the examiner doesn't want or expect it, it can't hurt to have it
> (unless you do it wrong).

Yes, and it is also just good operating practice, check ride or no. I
have it in my spreadsheet so that it calculates both CG locations and
all I have to do is enter the fuel expected at takeoff and at landing.

Balance isn't something to be taken lightly. Being 200 lbs over gross
typically isn't a big deal (I'm NOT recommending it), but being an inch
aft of the CG limit can be fatal.


Matt

[Matt Whiting]

Jose wrote:
>> Somebody mentioned that the gear will make a 1/2" difference in CG. I
>> personally don't believe that, it's way too much.
>
> I showed the calculation. It's in the Arrow book.
>
>> But assuming it's true no airplane falls out of the sky by going from
>> the CG on the aft limit to 1/2" past the aft limit.
>
> No, but with thinking like that, if you decided to fly an inch out of CG
> and ended up an inch and a half...

I don't see a half inch of change, but it is still a fair amount
(0.34"). Here is my spreadsheet calculation from my last flight.
Unfortunately, the formating from Excel gets hosed pretty badly.

The point is that nobody knows for sure how far past the aft limit is
too far for any given flight condition and operating past the aft limit
at all is just dumb. The only thing dumber is not even knowing that you
are aft of the limit.

Matt

Piper Arrow PA28R-3009 N3705T

Quantity Weight Arm Moment
Airplane empty 1552.65 84.53 131253.15
Oil 15.00 29.50 442.50
Fuel 50 300.00 95.00 28500.00
Pilot and front seat passenger 385.00 85.50 32917.50
Rear passengers 125.00 118.10 14762.50
Baggage 30.00 142.80 4284.00
Gear retraction 819
2407.65 88.11897493 212159.65 Gear down
88.45914066 212978.65 Gear up
Gross Weight (2500 max) Center of Gravity Total Moment

[gatt]

"Mark T. Dame" > wrote in message
...
> Newps wrote:
>>
>>
>> Bull****. Somebody mentioned that the gear will make a 1/2" difference
>> in CG. I personally don't believe that, it's way too much.
>
> You don't have to believe it. If it's in the book, that's what you use.
> It's not a matter of opinion. It is what it is.

The POH for this PA-28R has "Moment due to retracting landing gear = +819
in-lbs" beneath the CG Range and Weight Chart, so I'm going to plan
accordingly for the exam. Thanks for the heads up!

-c

[Jose]

> I don't see a half inch of change

Depends on your gross weight. The lighter you are, the more change
you'll see. I used 2000 lbs, and rounded up a bit.

Jose
--
There are two kinds of people in the world. Those that just want to
know what button to push, and those that want to know what happens when
they push the button.
for Email, make the obvious change in the address.

[Matt Whiting]

Jose wrote:
>> I don't see a half inch of change
>
> Depends on your gross weight. The lighter you are, the more change
> you'll see. I used 2000 lbs, and rounded up a bit.

That's true. I've never flown the Arrow that light as me and full fuel
is more than that!

Matt

[Mark T. Dame]

Jim Burns wrote:
>
> I don't think the magnitude of the CG change that is the emphasis of the
> DE's questions or teachings, rather the fact that it can change. I think
> this lesson is meant to point out the importance of a complete understanding
> of W&B as applied to each particular aircraft using the proper W&B and POH
> information.

Well put. That sums up my point nicely.


-m
--
## Mark T. Dame >
## CP-ASEL, AGI
## <insert tail number here>
## KHAO, KISZ
"To paraphrase Thomas Edison, programming is 10 percent inspiration
and 90 percent debugging."
-- C: The Complete Reference, Herbert Schildt