Two commercial questions

E_Dawg

Moderator
OK... got a few questions here:

1) Why is it that I always seem to be able to go faster with the prop at high RPM if the efficiency increases at lower RPM?

2) Let's say I own a plane and am acting alone. Can I transport paying passengers in my airplane if it's private carriage and 119.1 doesn't cover it?

3) Let's say I don't own a plane, but I have private carriage to transport... can I provide the plane by borowing or renting someone's?

Thanks.
 

pilot602

If specified, this will replace the title that
1) Faster does not equal more efficient. In fat most of the time the two are mutually exclusive. Low RPM settings are more fuel efficient because the prop is essentialy just a big gas pump (the faster it turns the more fuel gets "pumped" into the cylinders in order to make it turn that fast). Faster RPM settings get more air moving and thus propels the aircraft through the air with more veolcity but it takes more fuel to do it.

2) No. If you own the plane and anyone pays you - essentially - any amount of money the FAA considers it a "charter" op and without a 135 operating certificate you're in doo doo. The only way the private carraige thing would hold water is if your "customers" were providing the plane.

3) Again if you are providing the plane it constitutes a "charter" op. See number two for details.


As a commercial pilot about all you can do is what's outlined in 119 and or fly someone elses plane (either rental or owned) for them. If you provide the plane (either rental or owned) the FAA looks upon it as a charter service and not piloting services.
 

EatSleepFly

Well-Known Member
[ QUOTE ]
1) Why is it that I always seem to be able to go faster with the prop at high RPM if the efficiency increases at lower RPM?


[/ QUOTE ]

First off...Efficiency does not necessarily equal speed. [Pilot602 beat me to the punch, sorry for repeating...]

The higher the advance ratio of the prop(the distance the airplane moves forward with each turn of the prop), the more "efficient" it is. If you pull the prop way back to a low RPM, and leave the MP alone, the advance ratio will increase, and therefore, so will your efficiency. In other words, if you can maintain a given TAS by reducing RPM and increasing MP, you will have a lower BHP required and therefore lower fuel flow, with no loss in speed.

Fuel flow is a function of BHP (Brake Horsepower= what the engine is producing at the crankshaft). Speed is a function of THP (Thrust Horsepower= HP output after you take into account the efficiency of the prop).

The alternative is to reduce RPM, and increase MP to acheive a given BHP (and fuel flow), and take the increased effiency in the form of extra speed instead of lower fuel flow.

Make sense?
 

ananoman

New Member
In the higher powered piston aircraft, you can usually save several gallons per hour by flying at 65% instead of 75% power. Often you loose less than 10 knots. So the last little bit of speed cost quite a bit. A good example of this is the Cirrus SR22 vs the SR20. The SR22 has 310 hp and cruises about 180 ktas. The SR20 has 200 hp and cruises about 160 ktas. It is true that the SR22 weighs more and has an increased wingspan, but the drag increase from this is small. The extra 110 hp does not add that much speed.

As far as private carrage, this is a grey area. The standard answer is that pilots with 3 or fewer contracts on a long term basis have been found to be engaged in private carrage. Pilots with more contracts have been found to be operating illegal charter operations.

If you fly your lawyer uncle in your aircraft, and he is your only client, then you would probably be engaged in private carrage. If you fly anyone who ask in your aircraft, you are breaking the FAR's. There is a certain cargo company that does most of it's business flying car parts for the big 3 that is not listed in the 135 database. I have a feeling they are probably engaged in private carrage.

There is an advisory circular that clarifies private carrage, but I do not know the number. The best answer is to consult the FSDO prior to engaging in this sort of activity.
 

xdashdriver

Well-Known Member
[ QUOTE ]
2) No. If you own the plane and anyone pays you - essentially - any amount of money the FAA considers it a "charter" op and without a 135 operating certificate you're in doo doo. The only way the private carraige thing would hold water is if your "customers" were providing the plane.


[/ QUOTE ]

There have even been instances where no money changed hands and the FAA STILL called it an illegal charter operation because the pilot was receiving compensation in the form of flight hours. A stretch? Yup. Did the FAA win? Yup.

The best thing to do about the whole illegal charter thing is stay at a safe distance from it. Most of the time if you're asking the question of whether it would be legal, chances are the FAA have won cases to prove that it isn't. Don't forget that the FAA makes, interprets and enforces all their rules.

Ray
 

Minuteman

“Dongola”
Wellsir, drag roughly scales with the dynamic pressure, (air density)*(TAS)²/2, at low airspeeds and TAS*(drag force) is a work-rate (or power).

So that's: Power Required = (TAS^3)*(rho)*K
(rho is air density, K is some approximated, constant coefficient of drag that really should vary with the angle of attack, weight, mach number, etc.)

So let's say a 160hp engine gets you 110 KTAS. That gives a (rho)*K=1/8319. Now give your plane a 180hp engine with the same flight condition: 180hp*8319 = TAS^3, should give a whopping increase to 114 KTAS.

That's a 12% increase in power (and the accompanying fuel burn) for a 4% increase in speed. So, there's a definite fuel advantage to be had by flying slower (or really minimzing drag).

Is the horse dead yet?


I've never actually tried to compare this idea to actual performance numbers for anything other than Piper Cherokees. It should be roughly true for most bug smashers that stay below Mach 0.3 and I'd be interested to know if I'm full of it.
 

mcooper

New Member
Correct me if I'm wrong (and I know someone will if I am
), but don't the regs state that someone can compensate you up to half of the cost of the flight? In other words you can "share" the cost?
 

ready2fly

Well-Known Member
[ QUOTE ]
Yeah, thanks for clearing that up! So it uses disproportionately more gas to go faster.

[/ QUOTE ]
I can vouch for this one. This past weekend, I flew the Mighty Warrior from Tampa to Chattanooga, TN at 8000' (for the first leg) and 6000' (for the second).

On the first leg, I had the thing leaned out as much as I could without the engine dying. Had the EGT married up (or as close to married as I could get.....TN style
), and had the RPM's set JUST above red-line.

Used up a BUTTLOAD of fuel.

So, on the second leg, I leaned again - and flew at around 2500 RPMs.

A LOT slower comparitively, but burnt a lot less fuel per hour. Go figger.

Just my (one) experience.

R2F
 

MidlifeFlyer

Well-Known Member
[ QUOTE ]
OK... got a few questions here:
2) Let's say I own a plane and am acting alone. Can I transport paying passengers in my airplane if it's private carriage and 119.1 doesn't cover it?

[/ QUOTE ]Yes. Absolutely. If it's private carriage and if119.1 doesn't cover it, you can. Of course, that's the catch. Almost anything you can think of doing in this context would be considered public carriage. The question often comes down to the elisuve "holding out" concept.

"Holding out" doesn't have an FAR definition. Doesn't need one. It's one of the tradiitonal tests for the difference between "private carriage" and "common carriage" and goes back to well before the Wright Brothers' flight. It's use for FAA enforcement purposes is like the "only incidental to a business" test, applied and defined by FAA opinion and case law.

All it means is that you are letting the public that you are available for transportation. "The public" includes any segment of the public that you are trying to attract. And it doesn't have to be many. For example, if you are one pilot with a 172, how much business can you possibly do? You don't have to advertise either - word of mouth that people "know" you are available is enough.

In addition to reading though a couple thousand pages of FAA legal opinion and case law, probably the best bet is to look at AC 120-12A PRIVATE CARRIAGE VERSUS COMMON CARRIAGE OF PERSONS OR PROPERTY. It's available online at http://av-info.faa.gov/dst/120-129.htm

[ QUOTE ]
mcooper added:
Correct me if I'm wrong (and I know someone will if I am ), but don't the regs state that someone can compensate you up to half of the cost of the flight? In other words you can "share" the cost?

[/ QUOTE ]Not quite. There's also a "common purpose" requirement that's not stated in the regulation, but has been applied for years. Essentially, it means, that in order to share costs with your passengers, the pilot must have a reason for going to the destination (other than having fun flying there)
 

av8rmsu

Well-Known Member
[ QUOTE ]
Correct me if I'm wrong (and I know someone will if I am
), but don't the regs state that someone can compensate you up to half of the cost of the flight? In other words you can "share" the cost?

[/ QUOTE ]

I believe you are referring to private privilages...

FAR 61.113 (c) A private pilot may not pay less than the pro rata share of the operating expense of a flight with passengers, provided the expenses involve only fuel, oil, airport expenditures, or rental fees.


In other words...your buddy wants to fly to the football game this weekend and he pays for half the plane rental.
 

MidlifeFlyer

Well-Known Member
[ QUOTE ]
I believe you are referring to private privilages...

FAR 61.113 (c) A private pilot may not pay less than the pro rata share of the operating expense of a flight with passengers, provided the expenses involve only fuel, oil, airport expenditures, or rental fees.

In other words...your buddy wants to fly to the football game this weekend and he pays for half the plane rental.


[/ QUOTE ]But =only= if you want to go to the football game also (or have some other reason for being there)
 

MikeD

Administrator
Staff member
[ QUOTE ]
[ QUOTE ]
I believe you are referring to private privilages...

FAR 61.113 (c) A private pilot may not pay less than the pro rata share of the operating expense of a flight with passengers, provided the expenses involve only fuel, oil, airport expenditures, or rental fees.

In other words...your buddy wants to fly to the football game this weekend and he pays for half the plane rental.


[/ QUOTE ]But =only= if you want to go to the football game also (or have some other reason for being there)

[/ QUOTE ]

C'mon guys, aren't we breaking this down just a little to far? Talk about getting to the nitty-gritty.........jeez
 

av8rmsu

Well-Known Member
[ QUOTE ]
[ QUOTE ]
I believe you are referring to private privilages...

FAR 61.113 (c) A private pilot may not pay less than the pro rata share of the operating expense of a flight with passengers, provided the expenses involve only fuel, oil, airport expenditures, or rental fees.

In other words...your buddy wants to fly to the football game this weekend and he pays for half the plane rental.


[/ QUOTE ]But =only= if you want to go to the football game also (or have some other reason for being there)

[/ QUOTE ]

Let me clarify it a little bit....I'll be damned if I fly a friend of mine to a football game and don't go to the game myself.


But, let me ask this hypothetical question...

Let's say a friend of mine had to be in a wedding and wanted me to fly him there...I don't go to the wedding but pay for half of the plane, just doing him a favor and hanging out...would this break a reg.

And no I haven't done this
...all hypothetical.
 

Ophir

Well-Known Member
[ QUOTE ]
Not quite. There's also a "common purpose" requirement that's not stated in the regulation, but has been applied for years. Essentially, it means, that in order to share costs with your passengers, the pilot must have a reason for going to the destination (other than having fun flying there)


[/ QUOTE ]


Where is that written? I am not saying it isn't, I just would like to read ti and I can't find it on faa.gov.
 

MidlifeFlyer

Well-Known Member
[ QUOTE ]
Where is that written? I am not saying it isn't, I just would like to read ti and I can't find it on faa.gov.

[/ QUOTE ]Here's one mention of it from a 1985 FAA Legal opinion. It comes up in the context of an organization what was set up to try to match willing pilots and passengers so there are some definite commercial "smell" to the situation, so that the common purpose statement (highlighted in italics) is only part of it.

==============================
December 26, 1985

Thomas H. Chero
Vice President - Legal
AVEMCO Insurance Company
Frederick Municipal Airport
411 Aviation Way
Frederick, MD 21701

Dear Mr. Chero:

Thank you for your letters to this office, dated September 9, 1985, and October 23, 1985, respectively, concerning the actions of the Pilots and Passengers Association (PPA).

You are correct in stating that Section 61.118 of the Federal Aviation Regulations (FAR) prohibits private pilots from participating in PPA's operations. Section 61.118 provides that a private pilot cannot act as pilot in command of an aircraft that is carrying passengers for compensation or hire unless the flight falls within one of the four listed exceptions in 61.118(a) - (d).

Section 61.118(b) allows a private pilot to share the operating expenses of a flight with his or her passengers. Additionally, the FAA has interpreted 61.118(b) so that the only allowable share-the-costs operations are those which are bona fide, that is, joint ventures for a common purpose with the expenses being defrayed by all passengers and the pilot. Nor does Section 61.118 permit pilots who want to build up time toward their commercial pilot certificates to carry expense sharing passengers to a destination at which they have no particular business. (emphasis added)

PPA pilots apparently would not share in the expenses of the flights they would undertake. It also appears that PPA pilots could be flying to destinations at which they had no particular business. The PPA system is not a casual one of an individual pilot wishing to take some friends or acquaintances with him on a trip. The PPA system would violate the letter, as well as the spirit, of Section 61.118.

Even if the pilot bears an equal share of the expenses with his or her passengers and indeed has his or her own need to fly to a particular destination, yet another problem arises. Since PPA's passengers would be solicited for flights by PPA from a broad segment of the general public, we conclude that each pilot carrying paying passengers from PPA would probably be engaged in common carriage. This means that each pilot would become an air carrier subject to the certification and operating rules of Part 135 of the FAR.

We appreciate your calling our attention to this matter.

Sincerely,

/s/

John H. Cassady
Assistant Chief Counsel
Regulations and Enforcement Division
==============================
 

MidlifeFlyer

Well-Known Member
[ QUOTE ]
But, let me ask this hypothetical question...

Let's say a friend of mine had to be in a wedding and wanted me to fly him there...I don't go to the wedding but pay for half of the plane, just doing him a favor and hanging out...would this break a reg.

[/ QUOTE ]Technically yes. Are you likely to get caught? Probably not. Unless, of course, (a) you did this all the time or (b) there was an accident and your friend mentioned the arrangement in the investigation.
 

av8rmsu

Well-Known Member
[ QUOTE ]
[ QUOTE ]
But, let me ask this hypothetical question...

Let's say a friend of mine had to be in a wedding and wanted me to fly him there...I don't go to the wedding but pay for half of the plane, just doing him a favor and hanging out...would this break a reg.

[/ QUOTE ]Technically yes. Are you likely to get caught? Probably not. Unless, of course, (a) you did this all the time or (b) there was an accident and your friend mentioned the arrangement in the investigation.

[/ QUOTE ]

Well let's say it is my dad then...I still pay for half. Is this stillbreaking a reg...

If this is breaking a reg...what's the point of getting a PPL.

I guess I am just playing "devil's advocate"...just trying to learn, not trying to argue.


I really don't understand where the FAA gets off on translating some of these regs. LOVE ME SOME FAA
 

MidlifeFlyer

Well-Known Member
[ QUOTE ]
Well let's say it is my dad then...I still pay for half. Is this stillbreaking a reg...

[/ QUOTE ]I'd say probably not. A flight that fulfills a family need is by definition personal to you. And even governments try to stay out of family business. [ QUOTE ]
If this is breaking a reg...what's the point of getting a PPL.

[/ QUOTE ]That's different for different people. But it's definitely =not= to charge people anything for flying them around for their purposes — that's what commercial pilots get paid for.[ QUOTE ]
I guess I am just playing "devil's advocate"...just trying to learn, not trying to argue.


[/ QUOTE ]It's actually a very good point. The FAA gets to interpret these regulations because they wrote them.


I sometimes look at it this way:

The FAA doesn't want private pilots engaging in commercial activities. It could have simply made a flat rule for private pilots: Do what you want, but you can't get a penny for it. But that would be silly. After all, if me and my buddies go for a long weekend in a car, we'll probably end up sharing the expenses of a trip. Why should an airplane be any different?

So they permit expense sharing. But if they don't also tie it in to purpose sharing, what's the difference between you and an air taxi or private carriage operation that operates at a loss?

And after all, do you drive people around town and charge them for 1/2 the gas? And if not, what's that drivers license for?
 
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