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You're right. My plane was polished aluminum and the dents didn't look too bad on it. The shiny aluminum helped. I do think the dents detract significantly from the value so use that in negotiating. The plane is probably OK, but it's a buyers market. If the seller doesn't want to negotiate, just keep looking. The right plane at the right price will show up soon.

It may fly just fine but during our travels, you sure use more gas than I do.



Jim

Those dimples make golf balls fly better, why not my plane?

Regarding dimples on an airplane. The Mythbuster did a program were they compare the fuel mileage of a smooth skin car with that of a dimpled skin car. The dimpled skin car got 10% better mileage.

HOWEVER Dimples on an airplane DO NOT improve mileage or anything else. After the show I was tempted to "dimple" my plane but thought to ask my nephew about it. He is an aerospace engineer and works at the wind tunnel at Langley for NASA. He is a true rocket scientist.

He explained to me in terms I could not begin to understand that the airflow around a car (and a golf ball) is basically turbulent and the air flow across an airplane is basicallty laminar. The effects of the dimples is totally different on the laminar airflow.

I did not dimple my airplane.

I know just enough about this to be dangerous. I hope someone with true knowledge can expand upon the matter.

I'm just kidding, of course. I would buy a dimpled plane, but it would have to be at the right price. That damage does detract several thousand dollars from the list price. It is only worth getting the plane for the right price, what that number is depends on the overall airplane and is hard to judge without seeing the plane in person.

The other thing I would advise is to make sure the 150 is the right size plane for you. It was barely OK for me at 6'1", and not useable for my son at 6'5". The yoke would hit his legs. Cabin size was the main reason I switched to a 172. Even for me, it was not the easiest thing to climb in, though once inside i was Ok if there was no one else in the plane. With my airplane partner and I inside, we were pretty much shoulder to shoulder. On the other hand, the plane fit the person I sold it to like a glove. He was much shorter and had to slide the seat pretty far forward. For him, the panel on the 172 was too high and obstructed his view.

That would describe me. I'm 5'5" and the 152 fits me perfectly. I have about 20 hrs in a 172. I have problem seeing over the panel. If I raise the seat, then the yoke is in my lap.

OK, you asked for it.

Dimples are just another type of vortex generator. As on a wing, they induce turbulent flow in order to keep the flow stuck to the surface as far as possible on the 'back' side of the body. This results in a reduction in the size of the low pressure region on the backside as the high pressure flow wraps further around the body. With less area of low pressure behind it, the difference in forces on the body from front to back is also reduced. This differential pressure force pushing back on the body in the direction of the flow is thus known as 'pressure drag.'

On a body that is fixed in orientation to the flow, like cars and planes (well - most of the time anyway ), the VG's are useful only in certain places on the body. A golf ball spins in flight, so the dimples are placed all over the body so they are where-when they need to be.

Part of my senior project was going to be testing the drag reduction from various configurations and locations of 'dimple tape' on a typical strut section in the low speed wind tunnel, so I did some research into what was already known. Unfortunately, the project turned into a wind tunnel flow field survey to check the wind tunnel itself. We ran out of time for the dimple test.

Golf ball vs C150

My nephew sent me this article on the effect of dimples.
http://www.aerospaceweb.org/question/aerodynamics/q0215.shtml

Which leads us to the question: Which is better a golf ball or a C150?

A C150 is cheaper (espically when you tend to lose many golf balls per round).

You do not have to rent a cart with a C150.
You cuss a lot less
No green fees
Never lost a wager on a 3 foot C150
Do not have to buy my wife a nice present each time I fly (she does not like golf).
Do not have 6 C150's in my bag (each one a newer improved version of the last one)
I have never thrown a C150 into a lake
Don't have to dress funny to fly (or in some cases I have heard of You don't have to dress at all).
You can fly at night
You only have to get lessons every other year

Its funny I think I can not afford to play golf and my friends think they can not afford a C150.

We may need to move this to another thread. Sorry

Terry,

Great comparison - and risking serious thread creep, I couldn't help but notice this sentence from the article: "The reason we do not see dimples on other shapes, like wings, is that these particular forms of boundary layer trips only work well on a blunt body like a sphere or a cylinder."

Thinking of the front end of a 150, maybe it should have dimples...

I bought my Cardinal with some very noticeable hail damage; well over 100 dings of various sizes. In the time I owned it and flew it a little over 1000 hours, most all of the dings simply went away. When I sold it, I disclosed the hail damage. The buyer asked me to show the dings to me; it took some looking to find the few that were left.

Warmest regards,
Rick

Welcome Brian. I spent the better part of a year looking for a 150 to purchase. I joined the club about halfway through the process. It was a good move. The accumulated wisdom and experience found among the members here and the clubs type related resources are without peer and are invaluable in helping with your search.

I eventually purchased my plane from another club member, a very good decision. My 2000 mile cross country to bring the plane to it's new home was a great adventure.

Like Carl said, resist the urge to rush into a buy. Avail yourself of the wisdom and insights found here and you will do fine.