size prop seagul decathlon 30?

[tizdaz]

Hi guys, I have a seagull decathlon 30 which has a LEO .46 plant, what's an ideal prop for this for a steady flight? at the mo it has a 12x7 prop but not flown yet, any info much appreciated, thanks 🙂

[Denis Watkins]

Everyone on here knows that it is " tin hats on " to speak about props, as there is always someone waiting in the wings, to swoop in with a comment, as they know better.

Your prop choice is narrowed by where you fly. If you are in a noise sensitive area, then a 12 x 7 will certainly hold the revs back.

To get off the ground smartly, perhaps, thick grass, normal conditions, then 11 x 6.

To move more quickly in the air, and perhaps quieter, then a 12 x 6.

There is more to consider with good ground clearance, but try an 11 x 6 for a good few flights and you might just like it.

[Jon H]

Prop selection is more of a black art than almost anything else but in general terms a 'slow' model like a decathlon will need thrust more than speed and this generally means larger diameter and finer pitch. 

 

Denis's points above are completely valid and i would agree that starting with an 11x6 and then trying a 12x6 would be a totally reasonable thing to do. I would recommend APC props due to their greater efficiency than master airscrew. 

[tizdaz]

13 hours ago, Denis Watkins said:

Everyone on here knows that it is " tin hats on " to speak about props, as there is always someone waiting in the wings, to swoop in with a comment, as they know better.

Your prop choice is narrowed by where you fly. If you are in a noise sensitive area, then a 12 x 7 will certainly hold the revs back.

To get off the ground smartly, perhaps, thick grass, normal conditions, then 11 x 6.

To move more quickly in the air, and perhaps quieter, then a 12 x 6.

There is more to consider with good ground clearance, but try an 11 x 6 for a good few flights and you might just like it.

Hi Denis,

I fly at a large open area that my club has away from residential areas so noise isn't an issue 🙂 I bought my decathlon used and it had a 12x6 prop on it (which has seen better days so to speak!) so while at my LMS i asked them for advice and they recommended the 12x7 which i purchased. It wasn't until i got home to do more research i noticed there wasn't really a clear answer on the "best" as you already pointed out.

 

So as im still learning to fly, is a 12x7 prop ideal or would you recommend the 11x6? cheers!

 

9 hours ago, Jon - Laser Engines said:

Prop selection is more of a black art than almost anything else but in general terms a 'slow' model like a decathlon will need thrust more than speed and this generally means larger diameter and finer pitch. 

 

Denis's points above are completely valid and i would agree that starting with an 11x6 and then trying a 12x6 would be a totally reasonable thing to do. I would recommend APC props due to their greater efficiency than master airscrew. 

yeh i definitely want more power than speed as I'm still learning to fly etc 🙂

[Outrunner]

Tizdaz Just because your flying field is well away from residential areas you should not be disregarding noise issues. At minimum your club should enforce BMFA guidelines. Too many flying fields are lost through excessive noise. Just because people don't live near your field doesn't mean they aren't going to hear you and object.

 

 

 

[Jon H]

Outrunner is right. My club has no noise limit but when the exhaust fell off my Enya 155 it was LOUD and i decided not to fly it any more. I was told it was fine, but i wasnt happy. I would not expect your engine to give too much trouble. 

 

Anyway if you are learning you might find that a 13x5 suits the model well if you are trying to keep the speed under control. 

[tizdaz]

On 15/08/2022 at 22:18, Outrunner said:

Tizdaz Just because your flying field is well away from residential areas you should not be disregarding noise issues. At minimum your club should enforce BMFA guidelines. Too many flying fields are lost through excessive noise. Just because people don't live near your field doesn't mean they aren't going to hear you and object.

 

 

 

the club I've joined has been around for over 60 years & fly IC, i don't think my .46 with a silenced muffler will be an issue especially as turbine models are flown ! & im also 100% certain they  adhere to all the BMFA regulations including noise  😉  & there is also a moto-X track nearby that is used regulary, im sure if noise was an issue, then the motoX track would would not exist! But thanks for your input regarding what type prop i should use! 😄

Edited August 16, 2022 by tizdaz