Prop diameter and ground clearance

[skippydiesel]

4 hours ago, FlyBoy1960 said:

it is a legal requirement, I found it now in the  FAA website.

https://www.govinfo.gov/content/pkg/CFR-2010-title14-vol1/pdf/CFR-2010-title14-vol1-sec25-925.pdf

it is 7 inches, not 6 inches, I did make a 1 inch mistake.

there is also a link which I can't copy to a PDF regarding LSA aircraft which you are welcome to find on Google as well.

FAA does not have jurisdiction in Australia. Having said that their opinion is worth considering.

 

CAA is the Australian equivalent - what, if anything, is their ruling?

[facthunter]

 Well I've gone this far without actually knowing. I flew a lyc 235 engined C-150 and it would cut grass if you weren't careful. Your prop will let you know if it's too low. You can cut grass with a tailwheel plane if you position the nose too low on take off or go around. DC 3's have bent props braking.  Nev

[onetrack]

As the original poster and question asker is based in FLORIDA, I'd have to opine that FAA rules apply to his aircraft.

[skippydiesel]

15 minutes ago, onetrack said:

As the original poster and question asker is based in FLORIDA, I'd have to opine that FAA rules apply to his aircraft.

Fair enough - never thought to check out the original posters locator - well done.

[FlyBoy1960]

2 hours ago, skippydiesel said:

FAA does not have jurisdiction in Australia. Having said that their opinion is worth considering.

 

CAA is the Australian equivalent - what, if anything, is their ruling?

Look on the google, its easly. 

 

Generally any ICAO country will have almost identical rules and standards for the plane design features. That way you can fly internationally and be legal.  Imagine (just using a number i have made up) if jet engines in Europe needed 1m of ground clearance but Australia was 1.5m.  It would mean the plane with 1m clearance couldnt operate in AU airspace (even if on overflight!).  Hence the word of the 80's,   harmonisation!

[skippydiesel]

24 minutes ago, FlyBoy1960 said:

Look on the google, its easly. 

 

Generally any ICAO country will have almost identical rules and standards for the plane design features. That way you can fly internationally and be legal.  Imagine (just using a number i have made up) if jet engines in Europe needed 1m of ground clearance but Australia was 1.5m.  It would mean the plane with 1m clearance couldnt operate in AU airspace (even if on overflight!).  Hence the word of the 80's,   harmonisation!

You & I might expect this to be so but just look at the significant differences between Australian & US  small recreational aircraft rules.

 

When you get into commercial aircraft that can easily/routinely fly between nations - I would expect a high degree of your "harmonisation!"

[facthunter]

RAAus stuff have dispensations which only apply HERE. Your RAAus Certificate is worth nothing overseas.  Nev

[skippydiesel]

Nev - Very confused - are you responding to someone/ a topic on his thread?

[LoonyBob]

29 minutes ago, skippydiesel said:

Nev - Very confused - are you responding to someone/ a topic on his thread?

I think he's replying to you... he is making the point that "state regfistered" (VH in Oz) aircraft meet design standards that are acceptable to ICAO, and very equivalent, whereas sub-ICAO airworthiness standards are "national standards", and have no portability. ALL Recreational Aircraft are deemed to be non-ICAO, which is why they're allowed pilots with a sub-ICAO medical standard...

[BC0979]

Yes, I am in Florida, USA so FlyBoy is correct. I am required to have 7" minimum ground clearance.

15X6-6 tire deflated plus the bottoming out of the nose gear to the stops. I will need to check this.

I fly off a grass field so nothing will save me if I bury the nose gear in a gopher hole....

Thanks again for all the input.

[skippydiesel]

13 hours ago, LoonyBob said:

I think he's replying to you... he is making the point that "state regfistered" (VH in Oz) aircraft meet design standards that are acceptable to ICAO, and very equivalent, whereas sub-ICAO airworthiness standards are "national standards", and have no portability. ALL Recreational Aircraft are deemed to be non-ICAO, which is why they're allowed pilots with a sub-ICAO medical standard...

Speculation ; Where VH do experimentals fit in  "state regfistered" (VH in Oz) aircraft meet design standards that are acceptable to ICAO,"?

[Garfly]

 

26 minutes ago, skippydiesel said:

Speculation ; Where VH do experimentals fit in  "state regfistered" (VH in Oz) aircraft meet design standards that are acceptable to ICAO,"?

Maybe here?

 

https://www.casa.gov.au/sites/default/files/2021-11/experimental-certificates-coa-02-protocol.pdf

[aro]

49 minutes ago, skippydiesel said:

Speculation ; Where VH do experimentals fit in  "state regfistered" (VH in Oz) aircraft meet design standards that are acceptable to ICAO,"?

They don't, and you can't just fly them to another country like you could with a normal aircraft.

Same applies to the USA AFAIK, the design standards quoted above do not apply to experimental category aircraft.

[facthunter]

 A STOL plane with an extended nose strut/wheel could become quite dangerous. If you go from a 912 to a  non geared flat motor you have lost about 5 inches of prop clearance. Nose wheels are not strong on any plane and if a lot of weight is on it, you can't control the plane directionally..  Nev

[skippydiesel]

32 minutes ago, aro said:

They don't, and you can't just fly them to another country like you could with a normal aircraft.

Same applies to the USA AFAIK, the design standards quoted above do not apply to experimental category aircraft.

So where does BC0709's Savannah S fit in all of this - experimental?

[FlyBoy1960]

9 minutes ago, facthunter said:

Nose wheels are not strong on any plane and if a lot of weight is on it, you can't control the plane directionally..  Nev

Sorry Nev, this is the strangest comment i have ever heard ? 

 

You can still steer a plane with a lot of weight on the nose if its properly designed ? 

 

There are actually design standards for all of the loads expected with a 1.75 load factor above design for compliance.

[facthunter]

It's NOT strange IF you think about it. Have you heard about wheel barrowing? . When nosewheels first became almost universal there was a spate of wheelbarrowing incidents and still happens when people approach too fast.  Nosewheels ARE relatively fragile and never strong enough to handle large loads from any direction. There are plenty of examples 4 Jabiru's wiped their nosewheel off at Avalon one day because they accepted a downwind landing . It only takes a rabbit hole or a bad bounce recovery.. A plane sitting at a high nose attitude on all it's wheels will lift off before you want it to on a crosswind takeoff..  Nev

[LoonyBob]

12 hours ago, Garfly said:

 

Maybe here?

 

https://www.casa.gov.au/sites/default/files/2021-11/experimental-certificates-coa-02-protocol.pdf

 

12 hours ago, skippydiesel said:

Speculation ; Where VH do experimentals fit in  "state regfistered" (VH in Oz) aircraft meet design standards that are acceptable to ICAO,"?

A "special certificate of airworthiness" is not recognised by ICAO; if you cart a VH aircraft to another country and want to fly it, it must have a normal Certificate of Airworthiness and a current Maintenance Release. If the other country has a mechanism for aircraft not certified against an ICAO recognised design standard (e.g. the UK, USA), then they'll have a mechanism for making their own determination of airworthiness, which may require having one or more of their "approved" people vet the thing. LSA, despite being accepted in some form by many countries, is a multiplicity of national standards... the Savannah S is an LSA machine, complying with the EASA definition of LSA, which I believe to be accepted in Australia.