This is why the numbers are tampered with, just to set a lower bound below which the manual doesn't want to go.

The only way to know what your plane ACTUALLY does is to measure it. Today, with GPS data loggers and video cameras, this is much easier than it was.

BTW, this also was done to the MU2 charts many years ago. Despite what the MU2 can actually do, the charts are really pessimistic, so much so they are often longer than my Citation for distances. The MU2 chart has also been tampered with to basically set a lower bound.

And to answer the question, I would like to have graphs or charts that represented the plane's actual performance, not manipulated.

Mike C.

I haven't looked at the link, but those two concepts violate the laws of physics.

The slowing down equation is F=ma. Force=mass x acceleration. Or, rearrange it as acceleration = force / mass. The brakes are capable of delivering a certain amount of force, so if you increase mass, acceleration is smaller. (Acceleration is negative in this case.)

Spoilers create a certain amount of down force and drag for a given speed. It's dependent on airspeed and independent of weight.

I disagree with the FAA policy that allows publishing obviously false numbers, as long as they are false in the right direction. They should at least say in the POH that the performance is "at least as good as" when that is what they mean with certain numbers. When someone realizes the book is far conservative on some numbers, logic suggests others are too, which may not be the case. Another example of the FAA looking at things from an ivory tower and not accounting for how the real world and real people work.

The C340 RAM VII STC has performance numbers for the higher gross weight, since Cessna obviously never did those. They left the rest the same, which they were allowed to do since with the extra power it would at least meet those. This makes the entire performance section wrong. At a minimum, they should require disclosing this.

Why not just say your airplane requires a 10,000 ft runway and to hell with the performance testing? Save a lot of money. Marketing could wink at people.

Not exactly correct but close.

The gear does have a ram air feature as seen in this one on a Bravo:

But there is no brake or clutch. As soon as the gear is lowered, the ram air starts helping turn the wheel.

But there is also a bleed air feed, that's the silver hose you see. This provides bleed air to get the wheel up to speed if ram air is insufficient.

There is also a speed sensor and lights on the panel to indicate minimum and maximum RPM has been reached. That's the black wire you see in the picture.

More on its operation in this document, especially section 3.2:

https://support.cessna.com/custsupt/con ... s_id=35450

Mike C.

I haven't looked at the link, but those two concepts violate the laws of physics.

The slowing down equation is F=ma. Force=mass x acceleration. Or, rearrange it as acceleration = force / mass. The brakes are capable of delivering a certain amount of force, so if you increase mass, acceleration is smaller. (Acceleration is negative in this case.)

Spoilers create a certain amount of down force and drag for a given speed. It's dependent on airspeed and independent of weight.

Not entirely correct.

The more mass, the more downforce on the wheels, the more braking force you can generate before the tire skids.

So mass does have an impact on braking.

If the brake stack can take the heat, the stopping distance is relatively independent of mass. More mass let's you apply more force, so the deceleration remains similar. This breaks down when the brake stack can't take the extra heat.

What really affects braking distance is speed. If force was constant, speed increase braking distance by the square. A 10% increase in speed is thus 21% increase in distance. But it is worse than that because the extra energy in the brakes will make them hotter and they become less effective the hotter they get, so 10% more speed might end up being 30% more distance.

Mike C.

Part of the "gravel kit" was reinforced flaps.

That still may need more repairs even so, though.

Landing a jet on gravel just seems wrong to me.

I'd love to be able to land on turf, but my Citation V manual says that needs a gravel kit even though there's no rocks, so that doesn't make sense.

The 501 was the last Citation able to land on turf out of the box (without a gravel kit). The later models are really no different in design, but the manuals got restrictive. Oh well.

Mike C.

Sorry, Mike.

[youtube]https://youtu.be/OAb8BhxI3kQ[/youtube]

That's okay, when I am cruising 410 knots for the same fuel flow as a 501 going much slower, I get over that envy for turf capability pretty quickly.

Mike C.

I never gave much thought to the Piaggio P180 before, but it will do almost 400 knots. And it does grass strips out of the box.

In fact I was just on the phone with a P180 driver here in Kuwait. He flies single pilot for a local businessman. After a few minutes of conversation he suggested I should fly with them as a safety pilot. Not sure how that's going to work since I still haven't done the multi checkride. Plus I have a daytime job and a family. Pretty tempting though.

The most interesting piece of info was that they were able to get insurance through a European insurance company for a fraction of what it would cost in the US, even though the plane is N-registered. I need to find out what the exact terms of the insurance are. Probably they are not allowed to fly in US airspace, but I'm not sure.

It is very common that, after having flown in a Piaggio, either in the cockpit or the cabin, people wonder why there are only 230 of those around the world. Speed, cabin room, pressurization, cabin noise, fuel efficiency, operating ceiling are all unbeatable.

Well, I know why, but that could be a subject for the Piaggio forum.

For me, it was the $250k gear overhaul that made me stop wondering.

I can go a long way in my inefficient plane with over $200k of fuel.

Re:Piaggio

That overhaul doesn't have to be done for part 91. There is also a little competition in that market now so it no longer costs 250k.

200k does not buy you that much gas BTW. About 185 hours worth in Mike C's V.

I just ran the numbers on a Citation Ultra. I fly Piaggio 200hrs per year. Ultra would have been about 180 as it is a little faster and all my trips are long. Using fuel average of $6, the Ultra costs about $80k more per year to run than the Piaggio over the same distance.

At around 200 hours per year, the Ultra maint program is actually worse than Piaggio b/c you cannot use the low utilization programs that a lot of folks take advantage of with the old citations.

If gas is always $4 gallon, the Ultra starts looking more interesting. Given our elected officials policy of believing low cost hydrocarbons are going to end the world too soon, I am betting we will not see sustained low cost Jet A ever again. Over a 10yr period, that gives the Piaggio a nice tailwind operationally while also giving one a simple airplane to fly that feels modern, a cabin comically larger than anything else SP, no type rating and the safest GA record ever (no fatalities in 30 yrs).

Piaggio fills a unique niche in the market. Hopefully parent company issues resolve at some point. Definitely not a plane for everyone, but like the MU2, those who know it and have flown it rave about it.

It's not so much that the single price of the gear overhaul turned me off, it's that the prices for something could be that high, and seem to be high across the board. It makes me think - how the &^% can a gear overhaul cost that much? What exactly gets done to the gear?

I'm several steps below the P180. That particular number convinced me that it was out of my league.

I haven't spoken to an owner who was unhappy with his decision. It's just not for me.

That's true.

But one has to also consider why the gear needs that overhaul, and that you likely need to eventually do it. So in reality, part 91 can extend the interval, but can't really avoid it ultimately.

Further, should you want to sell, and you have a timed out gear interval, you can only sell to another part 91 operator, not a 135 guy since they will need to get the gear done. Part 135 typically doesn't allow for skipping overhauls. The part 91 buyer will also discount you the gear overhaul regardless, like selling a plane with an engine over TBO.


My block burn is about 200 GPH, 170 GPH in cruise. I'd wager the P180 is about half that per hour. I go 10% faster, so per mile, I am burning 45% more fuel, or 90 GPH. $200K will buy me 40,000 gallons at my typical price these days, or 444 hours of flying.

If I start looking at the purchase cost, and assign any cost to capital, I am way ahead of buying a P.180. Part of that is because I got in before the big run up, but still, a P.180 is a major hull value increase.


My LUMP works up to 200 hours/year. It isn't a hard limit, either.

My maintenance costs have been quite reasonable due to my LUMP, my involvement, and my diligence. I'm probably saving $300/hour versus the service center "hands off" owner, maybe more. Not clear the Piaggio ecosystem would offer the same benefits such as ample salvage and PMA parts and lots of vendors to choose from.


Yes, lower gas prices really help the jet owner.


Hard to know. I suspect the high prices now will cause lots of efforts to not use it (like the rise of EVs, biofuels, SAF, etc) and that may end up making it cheaper in the future when those economies that depend on the revenue have to make sales (like the middle east). A recession could make it cheaper, too. Lots of upper pressure right now on oil prices, but also opportunity for that to decline in the future.


The P.180 is definitely an interesting plane. I'd like to get a ride in one someday.

The P.180 runway usage would keep me out of some airports. My V will land and takeoff in less distance, easily. Shockingly, I don't think the MU2 was that much shorter in runway usage.

The P.180 has the distinction of being hated for its noise more than the MU2. There are airports that banned the P.180 and not the MU2.

The P.180 doesn't have the healthiest company behind it. Support is a major factor in a plane's value. I'd worry about being an orphan. Even if Textron went away entirely (hugely unlikely), there are so many third party vendors supporting the Citation line, it would keep on trucking.

The prices for P.180 parts can be breathtaking, and that's from a jet guy!

Mike C.