repair tonini propeller

[tecnamdave]

Gday Dave here

 

I have a tonini propeller that has a small split or chip on the tip it is off my tecnam and i have replaced it with a new one

 

i would like a second opinion by someone that could posibly repair it and if so to be kept as a spare

 

i have asked around so far cannot find anyone qualified

 

 

[pylon500]

As a wooden propellor, it should be repairable at most prop shops on main airports, could be costly though?

 

This is one of my hobby horses;

 

Why do we have to stick to the propellor supplied by the manufacturer of the aircraft?

 

I've flown a couple of Tecnams and although they flew well, I thought in both cases that the props seemed a bit lacking and they tended to vibrate a bit.

 

I'm sure all Tecnams would perform better with a decent three blade composite prop?

 

Arthur.

 

 

[Guest pelorus32]

In Italy last year one of the guys we spoke to said that the "GT" in GT Tognini is the Italian initials for "never the same pitch twice". These guys hated GT Tognini props.

 

Interesting: I fly two P92 Echo Super aircraft which are about 6 months different in age, both with the same Tognini props. One aircraft reaches 5,000rpm on takeoff. The other can't quite get there - something like 4,950rpm. In both cases the performance is OK in climb and cruise but my understanding is that you are getting barely 90hp at those revs.

 

Regards

 

Mike

 

 

[hihosland]

not sure about wooden props

 

however small dings in composite props can be repaired with super glue and either baking soda ( soda bi-carb not baking powder) or micro balloons larger defects similarly with epoxy instead of super glue.

 

First clean the wound with MEK or acetone

 

then using a tooth pick apply as thin as possible a covering of super glue to seal, then apply with another tooth pick a thin layer of microballoons.

 

Slowly repeat the process layer by layer using a fresh toothpick for the super glue each time.

 

Then carefully sand back to the original profile.

 

All the usual qualifying statements apply

 

I'm no LAME nor specialist in composite repair.

 

However this process worked well for me on the Aerochute the prop of which being so close to the ground was very prone to damage.

 

Davidh

 

 

[Guest Harry]

In Italy last year one of the guys we spoke to said that the "GT" in GT Tognini is the Italian initials for "never the same pitch twice". These guys hated GT Tognini props.Interesting: I fly two P92 Echo Super aircraft which are about 6 months different in age, both with the same Tognini props. One aircraft reaches 5,000rpm on takeoff. The other can't quite get there - something like 4,950rpm. In both cases the performance is OK in climb and cruise but my understanding is that you are getting barely 90hp at those revs.

 

Regards

 

Mike

Very interested to read this. I am a new owner of a Bravo fitted with a Tognini prop and trained on a Sierra. The takeoff performance seems much less with the Bravo (not measured) and I wonder if it's the prop. Bruce Stark says the Airmaster constrant speed can be fitted but feels the difference would be attributable to ground effect.

Anyone have experience or comments?

 

 

[Guest pelorus32]

G'day Harry,

 

very interested to know what you think of the Bravo overall - it looks like a nice a/c.

 

As for the two aircraft I talked about in the material you quoted: Whilst they only reach around 5100 flat out in the cruise and just 5000 on t/o they both seem to perform OK - takeoff run is good, climb peaks at around 1000fpm and they lift a full load willingly.

 

As I understand it the Sierra and the Bravo have very similar wings, just as the Echo and the Golf do. That shouldn't account for the difference in performance, having said that the Echo/Golf seem to perform better on takeoff performance than the Sierra/Bravo by all accounts - a faster less "liftier" wing on the Bravo/Sierra type aircraft.

 

Please keep us posted on your Bravo.

 

Kind regards

 

Mike

 

 

[vk3auu]

If your aircraft has a 25 rego, you may need to get another prop signed off by a reg35 Engineer. You had better ask Techman for the right answer.

 

If the prop only does 5100 flat out, it probably has a bit too coarse pitch. OK for cruise perhaps but not so good for climb.

 

Theoretically, a 2 blade prop will be slightly more efficient, but the lower frequency vibration of the air against the windscreen is a bit more irksome.

 

David

 

 

[TechMan]

Why do we have to stick to the propellor supplied by the manufacturer of the aircraft?

I've flown a couple of Tecnams and although they flew well, I thought in both cases that the props seemed a bit lacking and they tended to vibrate a bit.

 

I'm sure all Tecnams would perform better with a decent three blade composite prop?

 

Arthur.

Arthur, while I agree with you, you actually know the answer. It is a certificated aircraft. It has been mentioned to me that Tonini's are somewhat out of balance from the factory, so if you have one, best balance it properly. It would be wise to undo the bolts every now and then anyway to release any possible pressure increase during the changing seasons.

 

On the other hand, get a REG35 to sign out a 3 bladed for your Tecnam and away you go, otherwise, build a Tecnam yourself from a kit and you can put whatever prop you want on it.

 

Chris