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View Full Version : A 70hr SS7 report form OZ.



rosslr
01-20-2016, 09:49 PM
Having now clocked up 70 hours since the first flight 2 mths ago, I thought it might be useful to reflect on what I have learnt, report a few stats, and indicate what I still have to learn.

1. What have I learned? First, the first flight was as others told me - just like flying the Stick and Rudder planes - if I hadn't made the effort to go and get instruction on their aircraft though there would have been a few surprises! And then there was the generosity of the Oregon guys who gave me a great days flying! (you are including as an honorary Oregon guy here Floog!) So, for someone with no other Kitfox time, it was a great investment of time and effort ... and fun! Having said that, our plane has some differences as well as a lot of similarities. For instance, my first flight was the first time I had flown the combination of SS7 with 912is Sport, Airmaster with 75"blades and 26" bushwheels and the specific instrument pack that I have installed. So rather than let the differences concern me, I concentrated on the similarities - same airframe, same wheels =same picture out the window. Prop and engine just varied the performance a bit so I just flew (and still do) conservatively. Next thing I have learned is that flying a tailwheel and wanting to maximise the STOL capabilities requires an additional set of skills form normal GA flying. And learning those skills is an ongoing program. I try to fly each day, record performance and what I have learned and set myself a lesson for the next day. I am pleased to say that I think I am starting to get a bit better at this type of flying. I have a friend with a Super Cub who has a cattle property not too far from here and he is very accomplished at bush flying and generous with his property. his time and expertise! He's no cowboy, and leaves me fully in charge of my learning but supports and challenges when appropriate. Lesson for me was to find someone who suites your learning style and work with them - distance the others who are willing but a nuisance!

I also learned to take the cowl off after each flight and check everything! easy to pick up little things early that way.

And getting the prop dynamically balanced smoothed things out a lot.

Learn your checklists, keep modifying them, and NO SHOTCUTS - especially when getting a little older!

I had a few little issues with the Rotax connectors for the airbox sensors and one of the fuel pump connectors - from researching on the web this seems like a well know issue - Rotax have provided a fix - but I don't really like it as the underlying issue of poor connections is still there-otherwise, it is a well designedengine and functions very well.

The Airmaster prop is great - very easy to use and service and I am imagining that it enables the good cruise speed even with the big tyres!

What else? Well, I knew this before we started building but the Kitfox is nearly impossible to overload or to load out of the WB envelope - nearly! However, Gayle and I can fly with full fuel and 68kg(150lbs) of luggage we are still under weight and in the WB envelop. Mind you, at those figures we have to be careful of performance. But not too many other similar designs can do that and still get the cruise speeds we do! Which brings us to a few figures....

The Stats:

Take off and landing all under 100m (320ft) - working on settings and techniques to max for each situation.

42kts (48mph) Stall, power off no flaps

38kts (44mph) Stall, power off 1 stage flaps

37kts (42mph) Stall, power off 2 stages flaps

32kts (36mph) Stall, power approx 2800rpm, full flaps

105kts (120mph) cruise, 5000rpm and 24/25" MAP

Fuel burn is about 15lt (3gal) /hr

Still to learn? - Heaps, but the main thing is to really get to know the aircraft and how to fly it for each purpose and to each set of conditions. I am a slow learner but that just means I have to practice more!

And to finish, a few pics ( everyone loves a few pics!)

I have installed VG's - cant say they make any observable difference to top speed nor stall speed. I do think however, that they make a difference to elevator authority on landing. They are from STOLSPEED - I actually went and visited the guy who makes them here in OZ - John Gilpin - a great guy to talk flying with and well worth a visit to his website where he has some interesting pics of flying in remote outback OZ and also of his adventure around the US.

Other pics are of my sunshades - just to remind you nth guys that there is a sun!

And another pic of how I have mounted the control boxes for the Lightspeeds - these are also wired with Lemo plugs and have a lovely, single and flexible.

Oh, and a pic of Gayle's old short stockings that make good covers for the fuel tank vents - in case they are ever forgotten the tanks will still be pressurised.

cheers for now

ross

kitfox2009
01-20-2016, 10:14 PM
Great job,Ross.
I am sure you folks will get many years and hours of pleasure out of your efforts. You have a fantastic area to fly in. I am sorry I was not able to take the time to get up from Lakes Entrance (camping with the grandkids) and the rest of the trip was all in south eastern Victoria. As you said though, Tasmania was spectacular. Could have easily spent the whole two months there. Maybe we will meet up next time I am down under.
Cheers
Don
Vixen C-FOXK 912UL IVO IFA

rosslr
01-20-2016, 11:53 PM
Chers Don - yeah, things got a little busy over the Dec/Jan period so it might have been problematic anyhow. I agree about Tassie and will be planning a flying trip there for sure - but for now, our first big one is going to up through the centre to the Kimberleys in about June. Bit of a contrast to Tassie.

cheers

ross

jrevens
01-21-2016, 12:06 AM
That was a great report, Ross! Your numbers sound very good to me. Thanks for the effort you take to keep this forum informed as you progress - it is appreciated very much!

Dorsal
01-21-2016, 05:14 AM
Nice write up, very impressed with the cruise @ 3GPH! (about half the burn I get for the same speed).

jiott
01-21-2016, 12:00 PM
Great numbers Ross!
That combo of 912is and Airmaster prop is impressive.

WWhunter
01-21-2016, 02:48 PM
Maybe it's Imperial gallons. (that would be 3.6 US gallons/hr.)
:) Even at that, it would be some pretty good fuel burn!! Sounds like what I get at under 5000 rpm.

rosslr
01-21-2016, 04:24 PM
I just used another conversion app. and got 3.9625807853722 USgals/hr. Sorry about that but we dont use US gallons nor MPH here so not familiar with the conversions - 15lt/hr is about what the rotax tables suggest - I think they suggest about 2-3lt better fuel consumption for the 912isSport than for the 912uls.

cheers

ross

WWhunter
01-21-2016, 05:20 PM
That is still great fuel burn rate! Just under 4 US gallons per hour cruising at 120 mph! That is great, basically getting 30 mpg! How are you liking the FI 912?

I have seriously been thinking lately of getting rid of all the various projects I have, and spending the money on either the 912iS or waiting until the newer 915 (?) comes out. It will be at least several years until I can get to the point of needing an engine so I am in no hurry.

I just guesstimated the 3.6, since I am close to Canada and I have a few gas cans with both measurements on them. I couldn't remember if they are 0.8/0.9 imperial gallons for a 1 US. gallon can.

Esser
01-21-2016, 05:54 PM
Just fuel inject your own 912 for way cheaper. http://www.sdsefi.com/aircraft.html

3.78 liters to the US gallon. 1 US Gallon is .83 Imperial (4 liters) When are you guys going to switch to metric like the rest of the world?

rosslr
01-21-2016, 06:11 PM
Hi Keith - you ask how I am liking the 912is sport- yep, it is very cool engine - smooth and seems really well matched to the Kitfox. I mentioned that the only issue I have had with it is a couple of the electrical connectors that would develop intermittent contact. The solution wast to tie them off tightly to ensure the male and female pins were in constant contact- since doing that I have not had any issues. Just got the 50 hr oil report back from Blackstones and all good - slight elevated readings on a couple of metals that they put down to the new engine. John Mc Bean suggests running the engine @ 5200rpm. My Airmaster is programmed to govern at 5000rpm and it seems smooth and happy there. I have tried it at 5200 and I dont see much difference. Will keep experimenting with that. The Fuel system is a little different and Kitfox has manufactured a very nice fuel manifold that houses the fine filter, pressure sender and by pass valve and that makes the fuel system between the pumps and engine very neat

So at this stage, very happy with it.

Josh, thanks for the confirmation on the conversion from Lt to US gals - and as for your probing Q about when the US will go metric ....... I think Canada will appoint you as Ambassador with diplomatic skills like that!!!

cheers

r

WWhunter
01-21-2016, 07:22 PM
Ross,
Thank you for the well written reply. Sounds like you are on your way to many trouble free hours.

WWhunter
01-21-2016, 07:24 PM
Just fuel inject your own 912 for way cheaper. http://www.sdsefi.com/aircraft.html

3.78 liters to the US gallon. 1 US Gallon is .83 Imperial (4 liters) When are you guys going to switch to metric like the rest of the world?


Esser, are you using one of these systems? I had looked into them a while back but honestly forgot about it.

Maybe a pm would be better or another thread. I don't want to get off topic any further with Ross's thread. Sounds like he has built a very nice plane!

Mcgaero
01-23-2016, 10:15 PM
Hi Ross,

Great to read your thoughts on the first 70 hours, it's all usfull info for me!
I'm still making progress... We have a wedding comming up in a few weeks so I won't get much done in Febuary but I have 3 weeks off in March that will be Kitfox time.
You and Gail will have to make the hop across the hill one day!

rosslr
01-27-2016, 04:55 AM
Hey Ben,

All the best for the wedding - pass on our best wishes to Kath too!

I think it is great that there is someone on this site talking of fitting in getting married with finishing the build!!! Mostly I think we are a little older...... I wish I was doing this at your age...

And yes, we are looking at weather and hope to come over the hill as soon as the weather provides a reasonable envelope - isn't there is a big difference in the weather over your way to the weather here?!

so all the best for the big event - and best wishes for the wedding too!

cheers

r

Planesmaker
01-27-2016, 01:33 PM
Good to read your report Ross, 70 hrs in 2 months of summer!!!

Let us know when you want to come this way for a day. Tom & Marsha

rosslr
01-27-2016, 04:23 PM
Will do Tom. We are looking at good weather patterns - thinking of flying in Gheehi flats to camp overnight shortly so might keep coming to Tumut.

Did I see the Skyfox that you restored up for sale again? it looked like a bargain to me - what size engine did that have?

r

Mcgaero
01-28-2016, 01:20 AM
Thanks Ross, yes our weather patterns are a little different this side of the range. I often look at the weather over your side and can't believe where in the same state!

P Johnson
05-09-2021, 04:41 AM
Having now clocked up 70 hours since the first flight 2 mths ago, I thought it might be useful to reflect on what I have learnt, report a few stats, and indicate what I still have to learn.

1. What have I learned? First, the first flight was as others told me - just like flying the Stick and Rudder planes - if I hadn't made the effort to go and get instruction on their aircraft though there would have been a few surprises! And then there was the generosity of the Oregon guys who gave me a great days flying! (you are including as an honorary Oregon guy here Floog!) So, for someone with no other Kitfox time, it was a great investment of time and effort ... and fun! Having said that, our plane has some differences as well as a lot of similarities. For instance, my first flight was the first time I had flown the combination of SS7 with 912is Sport, Airmaster with 75"blades and 26" bushwheels and the specific instrument pack that I have installed. So rather than let the differences concern me, I concentrated on the similarities - same airframe, same wheels =same picture out the window. Prop and engine just varied the performance a bit so I just flew (and still do) conservatively. Next thing I have learned is that flying a tailwheel and wanting to maximise the STOL capabilities requires an additional set of skills form normal GA flying. And learning those skills is an ongoing program. I try to fly each day, record performance and what I have learned and set myself a lesson for the next day. I am pleased to say that I think I am starting to get a bit better at this type of flying. I have a friend with a Super Cub who has a cattle property not too far from here and he is very accomplished at bush flying and generous with his property. his time and expertise! He's no cowboy, and leaves me fully in charge of my learning but supports and challenges when appropriate. Lesson for me was to find someone who suites your learning style and work with them - distance the others who are willing but a nuisance!

I also learned to take the cowl off after each flight and check everything! easy to pick up little things early that way.

And getting the prop dynamically balanced smoothed things out a lot.

Learn your checklists, keep modifying them, and NO SHOTCUTS - especially when getting a little older!

I had a few little issues with the Rotax connectors for the airbox sensors and one of the fuel pump connectors - from researching on the web this seems like a well know issue - Rotax have provided a fix - but I don't really like it as the underlying issue of poor connections is still there-otherwise, it is a well designedengine and functions very well.

The Airmaster prop is great - very easy to use and service and I am imagining that it enables the good cruise speed even with the big tyres!

What else? Well, I knew this before we started building but the Kitfox is nearly impossible to overload or to load out of the WB envelope - nearly! However, Gayle and I can fly with full fuel and 68kg(150lbs) of luggage we are still under weight and in the WB envelop. Mind you, at those figures we have to be careful of performance. But not too many other similar designs can do that and still get the cruise speeds we do! Which brings us to a few figures....

The Stats:

Take off and landing all under 100m (320ft) - working on settings and techniques to max for each situation.

42kts (48mph) Stall, power off no flaps

38kts (44mph) Stall, power off 1 stage flaps

37kts (42mph) Stall, power off 2 stages flaps

32kts (36mph) Stall, power approx 2800rpm, full flaps

105kts (120mph) cruise, 5000rpm and 24/25" MAP

Fuel burn is about 15lt (3gal) /hr

Still to learn? - Heaps, but the main thing is to really get to know the aircraft and how to fly it for each purpose and to each set of conditions. I am a slow learner but that just means I have to practice more!

And to finish, a few pics ( everyone loves a few pics!)

I have installed VG's - cant say they make any observable difference to top speed nor stall speed. I do think however, that they make a difference to elevator authority on landing. They are from STOLSPEED - I actually went and visited the guy who makes them here in OZ - John Gilpin - a great guy to talk flying with and well worth a visit to his website where he has some interesting pics of flying in remote outback OZ and also of his adventure around the US.

Other pics are of my sunshades - just to remind you nth guys that there is a sun!

And another pic of how I have mounted the control boxes for the Lightspeeds - these are also wired with Lemo plugs and have a lovely, single and flexible.

Oh, and a pic of Gayle's old short stockings that make good covers for the fuel tank vents - in case they are ever forgotten the tanks will still be pressurised.

cheers for now

ross

Hi everyone,

I live in the UK and own an RV4 which is great for long distance flights and aeros so speed is not my main mission, but I would like to get the best performance possible out of the SS7 with a 912is Sport engine, my main reason for building the SS7 is I want to fly to the smaller microlight airfields (300m or less) that we have in the UK and the Kitfox SS7 looks a really fun aircraft to fly. I will be taking delivery of a SS7 kit later in the year and will be equipping my aircraft the same as Ross except for the propeller and tyres (desser), I will reduce the propeller diameter to the 70" Airmaster as I believe this will give me slightly better cruise but increase takeoff distance. The aircraft Ross built has a very nice cruise speed (105kts (120mph) cruise, 5000rpm and 24/25" MAP).

Does anyone else have this set up and do you see the same figures?

Am I right to reduce the prop diameter?

Regards

Paul.

Shadowrider
05-09-2021, 03:59 PM
It was an interesting read for sure. He didn’t notice much with the vg’s because they where placed to far back. If they where moved forward it would help a bunch.

P Johnson
05-11-2021, 11:13 AM
Thanks Dustin,

I was more interested in prop size selection and if those cruise figures are attainable with the set up I am considering.

Paul.