STi STOL vs SS7

[tjentzsch]

From what I understand, the STi has a different wing design over the SS7, but how much of a difference does this make in STOL situations and top end speed?

From what I gather, the STi will have reduced top end speed but better STOL characteristics, but buy how much of a margin over the SS7?

[Shadowrider]

Have you watched Trent’s videos? He talked about switching his wing to a STI wing. Nick is running his old wing, just barely flew with him. He plans on building a STI wing at some time. With that being said the “regular” wing is no slouch in the short field area. Nick said the STI wing does a lot better high and hot.

[tjentzsch]

Thanks for the reply. Ya, I have seen all of Trent's videos. I knew he had the STi wing, but perhaps I missed where or if he talked about the STOL differences between the SS7 wing and the STi wing.

Could you elaborate on what you mean by high and hot?

[Esser]

You lose 25mph in cruise but you stall 10mph slower with the STI wing

[tjentzsch]

Wow, that much cruise speed, yikes!

[Esser]

Yeah plan on 100mph cruise.

[tjentzsch]

Well, That answers what kit I am getting, SS7 :)

I give up a little stall speed for cruise, at least for no win my current thinking.

[Shadowrider]

Yeah 20 mph loss in top speed but 10mph reduction in stall speed. I think if your building as a cross country plane 7SS. If your not worried about getting anywhere fast STI. The STI climbs better heavy and high DA’s. Much thicker cord wing. Personally I think you lose 20 mph on top speed more because of the combination not just the wing, but monster shocks, big tires, cabane landing gear and not so much just the wing. I just flew with Nick and 95mph Cruise is what he is seeing. He has 7SS sti with the 7SS wing, (Trent’s old wing) not STI wing. He has 29” wheels and monster gear. Of course his gear is uncovered so he will pickup some speed there when he covers it. Regardless they are so fun to fly. Went out twice with nick and it was so fun to fly! His plane is sweet and he did a good job building it.

[tjentzsch]

That is awesome. I have yet to ride in one, no friends into aviation, so I am in uncharted waters here lol. Hence all the questions I post trying to figure things out.

There is a guy near SLC that I need to meet as he is currently building his plane and he's not that far from me.

Are you building or do you already have one? How did you meet Nick?

[Shadowrider]

I live in Mapleton,UT. I am building a STI and my brother, who is next door, is building an STI. I need to post some updates where we are, but we have been building since June. Goal is a year build time🤞 We met through Facebook. He started his right before we picked ours up. He built it in 5 months. Already has 100 hours on it. Crazy! They are so fun. Visibility is great. Crazy how much you can see. It’s been a long time since I have been low and slow.

[tjentzsch]

Very cool. Im up in Sandy, not far from Mapleton. Perhaps we could meet up sometime? I would love to see one in person and get a better feel for them.

Ya, 5 months is nuts. Wish I had the time and money of some of these guys. Well I have the time being single, but money, that one is harder lol. I have a plan to pursue this if it all works out, in about a year, I hope. One of my biggest challenges is finding a place to build.

[Shadowrider]

Anytime your welcome to come out. I think because #plametrentpalmer there is over a year wait. Put in a deposit and get a kit coming.

[tjentzsch]

Very cool, thank you. I will PM you my cell.

A year wait! wow. I wonder what Trent's kickback for all the business is lol.

[efwd]

A Trailer ride for his plane after an engine failure left him stranded in the middle of nowhere. "kickback"

[jmodguy]

Not to mention STi wings n gear, new interior and a sweet deal on a new engine!
Hey its all in what you negotiate! Trent undoubtably has given Kitfox a lot of recognition 👍

[Blackmon]

Looks like Trent is going with the 915 for his new power plant. I wonder how much of that speed he will get back with the spare horses.

[rocketman2tm]

Probably not much. Losing that much speed on the top end is not going to be overcome with power. Climb performance is what the 915 brings to the table for the STI.

[Esser]

I have a friend who cruised in his Rans S6 at 100mph. He then added draggy bush gear with shocks and 29's He also upgraded to and Edge Performance Rotax making 160hp. He now cruises at 115mph+

[Shadowrider]

Yeah with a turbo you will get a lot of speed back by just going higher and getting a higher TAS.

[jrevens]

I have a friend who cruised in his Rans S6 at 100mph...


I'm getting a pretty good handle on my 7SS cruise speed now during my Phase 1 test period. I've got a 912 ULS, 22" tundra tires (no wheel pants of course), and no special fairings other than the lift struts. I've tried to do some accurate speed tests lately - no wind, but still making runs in all directions. At 6500' MSL (approx. 1000' AGL) I'm averaging 121 MPH TAS at 5400 RPM. Would that be considered a reasonable cruise RPM? The airplane seems to really jump off the ground also - no real numbers yet. This is just me and pretty much full fuel, but it seems very similar to Stick & Rudder's 914 powered bird with Paul & I in it (at a lower altitude). I'm pretty pleased with that.

[KitKarson]

The correct link!

https://www.facebook.com/KitfoxAircraft/videos/2001937909869753/

[Esser]

I'm averaging 121 MPH TAS at 5400 RPM...

Seems about right to me John. Everyone seems to be in the 110-125 range with the Model 7 with the standard wing.

[tjentzsch]

That is sweet! I wonder how the SS7 with 912is would perfomr

Any takers what to do some science for us ;)

[Suprdave]

That kind of performance with the 915 Turbo and STI at 17,500 is pretty cool.

Auto-Pilot would be really worth the weight at that point.

[Shadowrider]

Anyone know how high a kitfox has been? I think John had mentioned the flight levels?

[Esser]

17,500 is the highest I’ve hear. 500’ short of flight levels.

[Shadowrider]

I will try and find the interview, but John mentioned they have had one up in the flight levels. I will file and take mine up to the flight levels when done with my GoPro😬

[PapuaPilot]

That would be nice to see. :)

I got mine up to 17,200' on a Phase 1 flight to find out what the service ceiling was. I took off at gross weight and kept climbing till it wouldn't go anymore.

[tjentzsch]

I will try and find the interview,...

Make sure to let me know, I want to see that!

[Ronin]

I know of one that went to 29k with a 914.

[Shadowrider]

Details? Please🙏

[Ronin]

Sure. A gentleman named Glen Saunders worked for Kodiak Research years ago. He was doing some testing on a 914 Kitfox. Not sure if it was a 4 or later model. On one flight he took it up to 29k. He said the engine had some left but the airframe and prop were out of steam. It ****ed out all the coolant and he had to deadstick it back to Ft. Lauderdale airport. Said it took a while to get down, like 20 minutes or more I believe?

[aviator79]

I will try and find the interview...

Are you going to equip for IFR? I think it would be fun to take my 914-powered Kitfox up into the flight levels for giggles, but I'm not going to equip IFR for the privilege. 17999 is good enough for me.

[Shadowrider]

Sure. A gentleman named Glen Saunders worked for Kodiak Research years ago. He was doing some testing on a 914 Kitfox...

That’s crazy. I wonder if it lost the coolant because the radiator over-pressurized because of the pressure differential because of low ambient air pressure?

[Shadowrider]

Are you going to equip for IFR?...

I thought about fully IFR and spoke to John about doing it but not worth the money to put a approach approved GPS in it for the hand full of times I would use it. Mostly low vis in the winter. . As far as going to the flight levels....I will have the equipment needed to navigate appropriately on a clear day. ;)

[aviator79]

As long as it's severe clear, nobody on the ground will know how you're navigating. Just make sure it's clear: there is little that is more embarrassing than cancelling IFR to avoid clouds. ;)

[Shadowrider]

Ha reminds me when the eclipse jet was first “certified” it was IFR certified but VMC only. Pilots said it was hard to explain why they had to deviate for weather middle of winter, trying to avoid clouds.🙂

[Hockeystud87]

Is there anyone with a STI wing on a Model 4? That would be a total beast I would think with a 100hp.

[coosbo]

You lose 25mph in cruise but you stall 10mph slower with the STI wing

Is this 25 mph cruise drop a result of the different wing alone? Or is this number also with a grove to cabane gear + tundra tires?