The question is if it is deceptive advertising or puffery based on a rare set of assumptions?

The question is if it is deceptive advertising or puffery based on a rare set of assumptions?

Yup, so likely puffery that is often seen.

cavet emptor!

Twin & Turbine aircraft "tests" the active winglets. Seem to have rather impressive performance. As one owner says: “It’s the most cost-effective improvement you can make to an already great plane,” he said. “I have CJ2 range performance but the cost of the winglets is 20 percent of the cost to upgrade to the CJ2.”

Article here:

http://twinandturbine.com/article/jet-journal-active-approach-better-performance/

If I was in market for a jet, I'd look really hard at the earliest CJ models with semi-steam that are easily upgradable to glass, and add a Tamarack system. That'd be a pretty bad-ass setup for less than $1million (in some cases)...

Look how pretty they make the CJ3 look, like a little mini-G650:

That article is marketing. No real test. There is no way the winglets save 20% on fuel apples to apples. The only way this is achieved is that they fly the non winglet airplane at max thrust and fly the winglet airplane at max range power. Thus most of the savings is the change in engine operating point. Flying the engine at the same power settings will NOT get you a 20% reduction in fuel on a trip. Absolutely no way.

They fail to mention some issues.

One, the landing distances increase by 67% per the STC supplement. This is due to using the stock airplane Vref numbers (the STC doesn't provide new landing distances) which cause the plane to float much further down the runway due to the larger wing span and area. Legally, this cuts out many airports. This is even worse for 135 operators who have a 60% runway requirement on top of that. This could mean that the book says a stock airplane needs 3,600 ft, but now the 135 guy needs 10,000 ft of runway (1.67 for the Tamarack, 1.67 for the 135 requirement, compounded). The mod is basically not workable for 135, which means the plane has lost market footprint if nothing else.

Two, if the active winglet system fails, and there are a lot of complex parts here unlike a passive winglet, you have to reduce your speed substantially. If Tamarack goes out of business or has reliability problems, your plane is crippled and perhaps unflyable with the system INOP and maybe even unable to be returned to stock status due to cutting structure for installation. The owner has tied their airplane's value and utility to the existence and support of a one product start up company. That doesn't have a good track record in aviation.

Mike C.

On this point only I do believe that Cessna will support the product. You can't Buy directly from Tamarack, only through a Cessna Service Centre. I'm certain there are planes on the production lines (M2s) having the winglets installed. Although it would be expensive I'm confident they will be supported.

Andrew.

Like adding ADS-B to an early glass panel Citation?

Much $$$$.

If I was interested in the winglets, I'd wait about 2 years to let the early adopters figure out the real story. See if there are problems, see exactly just how far they have been overpromised, learn the downsides, etc.

Mike C.

Like adding ADS-B to an early glass panel Citation?

Much $$$$.

If I was interested in the winglets, I'd wait about 2 years to let the early adopters figure out the real story. See if there are problems, see exactly just how far they have been overpromised, learn the downsides, etc.

Mike C.

Which either means you already paid for it, or you will pay for it with further ProPart charges, or if you sell your plane soon afterward, you will owe a ProParts balance and pay for it then.

In Proparts, you either pay money for parts you don't get, or they charge you if you use more parts than your balance. It is "no lose" for Cessna, and seemingly "no win" for owner.


My understanding is ProParts does not cover upgrades and non mandatory SLs/SBs.

Mike C.

That's not correct. I did dual GTN750 upgrade in Oz. Pro-parts have them covered. Interesting originally they said no because they did not do the upgrade, when I pushed that Cessna dont have a service centre here they agreed.

You are right there is no free lunch in jet ownership!!

My point about pro-parts was if they agree to cover them they will support them. So if something happens to Tamarack they will continue the support.

Andrew

There may be puffery in the fuel savings, but this is amazing if accurate.

[youtube]http://youtu.be/ldy2dWnMpb8[/youtube]

The data I got was ISA+18, FL400, 36 minutes.

The video lacks enough information to judge the performance increase. For example, takeoff weight, where ISA+18 was measured, and starting airport elevation.

Assuming this is a straight CJ (not CJ1, CJ2, ...), the book climb numbers for some example situations are:

ISA+10, FL390, 10400 lbs: 42 min
ISA+10, FL390, 9500 lbs: 31 min
ISA+10, FL410, 10400 lbs: 110 min (step climb)
ISA+10, FL410, 9500 lbs: 41 min

The book doesn't give numbers for greater than ISA+10.

Adding wing area will improve climb, that is a well known effect. Without more detailed numbers, hard to say if this was a minor or major improvement. At this high altitude, small changes in weight and temperature make a huge difference in ability to climb, so time to climb numbers would be very sensitive to wing area increase.

If you want to measure the time to climb to, say, FL350, the time to climb improvement for winglets is not very significant. The stock airplane does that in 26 minutes (ISA+10, 10400 lbs), so there just isn't a lot of time to be saved.

Tamarack is very good about providing the impression of great performance increase, but always seems to never give you enough information to check it precisely.

Mike C.

He said "Mesa" service center. I'm assuming KIWA at 1300'msl.