Any idea why they stopped making the evo?

Old guy that built ours had a harmon and an f-1 side by side under construction and I couldn't tell a bit of difference. He said the f-1 was a little more prefab for the novice but otherwise the same. With regards to the 35kt stall, I'll check it out again but I was power off and both the airspeed and the gps read 35kts. I'll video tape it next time for analysis. I've been using 85kts on final and sticking it on the mains.

Doug, Mustang versus Rocket thoughts?

I've contracted with an engineering company to produce the documentation required by our aviation authority. They say that now is a good time to add a few "while we're at it" items in the documentation, just in case.

For the Rocket owners out there, what would you have on your wish list? Retractable gear? Light turbine in the nose? (thinking TP100 from PBS here, not M601 ..)

The F-1 kits were built by HPA in Czechoslovakia. The design and fixtures were owned an imported by Team Rocket of Taylor TX. The kit price got so high that Mark could no longer make any profit.

Vince Frazier has taken over the project and kits are now available again. http://Www.F1aircraft.com

There is also a new wing in design, and yes, there is an RG option being considered.

The F-1 EVO is outwardly almost identical to a Harmon, except for the wing, but there are several subtle but fairly important differences. The Harmon is a modification of a RV-4 kit. The F-1 is a purpose built kit.

The Rockets all claim a 240 kt Vne. That is a HUGE number. The King Air 90s have a 226 kt Vne. But there are some caveats. The Rocket Vne is 240 KTAS, not KIAS. That means at that the is reduced 4.8 KIAS per 1000 ft of alitude. It is very easy to exceed that number at higher altitudes in a descent, or doing acro, and the have been some flutter events that resulted in major airframe damage.

Flying an aircraft with this much performance requires discipline. The RG version (unless they are able to increase the flutter margin) will require even more discipline. So far, I'm not aware that any of the low-cost EFIS units have a moving barberpole function like a turbine. It would be very useful in a Rocket and almost imperative in an RG version.

I love my Rocket, it is very easy to fly, but it is a much higher performance aircraft than an RV and as a result, the accident rate, read insurance premium, is much higher.

I have been flying my current Rocket for over 10 years. I never fly an airplane for 10 years. I have always moved up. The problem is, there is no place to move up to. For me it is the ultimate sport plane / IFR X/C cruiser.

I plan to wear this one out...

Hey William,

I wouldn't do anything to this airplane. Just get one per the plans and install the Lycoming. It definitely doesn't need retracts and would likely go a lot slower with that small 200HP turbine than a 300+ HP Lycoming.

Hi Doug,

How are people hurting themselves in the RV/Rocket types? Another question is, do you fly yours in the weather?

Mike

One Builder forgot to bolt the tail on completely and perished.

Most of the accidents aren't fatalities. Most are nose overs, and there have been some flutter instances, but, but most of them made it back to the airport.

For what it's worth, the Garmin G3X and G3X Touch will support KTAS Vne and show a barber pole. See page 34-96 of the Installation Manual:

http://static.garmin.com/pumac/190-01115-01_AF.pdf

Doug where did you find that limitation of 270 KTAS? It indeed is a big deal. I have an AFM and it only states the 240 KIAS limitation (but maybe I read it sideways). I also don't understand, from an aerodynamical perspective, why true airspeed would be limiting here?

It is not 270KAS, it is 240 KTAS. I got that from Mark Frederick that was the owner of Team Rocket. The reason why is because flutter is a function of TAS not IAS. It is hard to imagine, but the best way I can explain it this: If you are at 10,000 feet, on a standard day, in a Rocket with an Indicated Airspeed of 200 kts and flying in rain, the raindrops are hitting the fuselage at 240 KIAS or ~2% of IAS for every 1000 ft of altitude.

It will take a better aerodynamisist than me to explain why flutter is a TAS issue instead of a IAS issue.

FWIW, this is also true in the RV's as well. Richard VG has written several articles about TAS and Vne in the RV series.

Thanks Doug for the explanation. I'm a bit overdue for an aerodynamics refresher

I'm no engineer, but from what I understand the key concept is that thin air does a poor job of dampening vibrations and limiting flutter.

Fluctuations in the empennage cause displacement in the airflow around the plane, and - importantly - this airflow tends to limit those fluctuations. At lower altitudes, the dense air does a reasonably good job of minimizing fluctuations. But apparently at higher altitudes and speeds, the air is too thin to push back effectively (much more compressible
) so flutter risk goes up.

I'm not sure this effect is completely proportional to TAS, but apparently expressing Vne in KTAS tends to provide the right correction.

Appropriate article on the subject.

A very rudimentary explanation:

Flutter and TAS has to do with the speed of the air molecules hitting the airframe whereas indicated airspeed is the speed of the air hitting the pitot tube.

Both the airframe and the pitot tube get hit with the same speed. Indicated airspeed essentially takes volume of molecules or pressure into equation, so it is essentially a force indicator.