SkyRanger Swift/Nynja vs BushCat/Cheetah XLS

[revlis240]

Hello all!

 

I am curious about a comparison between the Skyranger Swift/Nynja and the new BushCat/Cheetah XLS. I know the BushCat is just an update on the Cheetah, and the Cheetah as a copy of the original SkyRanger, but what I am most curious about is as follows:

 

1) The BushCat claims a luggage capacity of 81 lbs! This is nearly triple what the Skyranger products claim. There is such limited information and pictures on both these planes, does anyone know how they did it?

 

2) The BushCat claims a cruise of ~105 mph/91kts but appears to be a lot heavier at MTOW. The owners seem to make the same claim, so they must have a cleaner design, or..?

 

3) The BushCat has a 24 gallon tank, the Nynja has to be "upgraded" to a 22 Gallon tank, but I think the BushCat refuels from the outside, anyone confirm?

 

4) The Nynja offers folding wings, does anyone know if the Bushcat can accept the modification?

 

Thanks guys!

 

Abe from California

 

 

[gregrobertson]

Not sure I can help you a lot Abe as I am not familiar with the Bushcat. The Cheetah is just a knock off copy of the Skyranger and it wouldn't surprise me if they have also copied the Nynja.

 

At present the Nynja has a fuel capacity of 90 litres in an aluminium tank behind the seats. We are working on wing tanks at present which should be a big advantage as it will get the weight out of the fuselage. a full tank in the Nynja is just on 80 kg which with a bit of luggage (10-15kg) and a couple of 90kg people puts us just inside the aft CofG limit. The wing tanks will be right on the CofG and will fix that problem. I am hopeful of getting 55 litres each side. Watch this space, hope to have them flying in a couple of weeks.

 

Greg.

 

 

[revlis240]

Greg!

 

Thank you so much for the reply, I joined this forum just to talk to you lol. You have no idea how excited I am over this, because I actually bought a partially completed Sonex kit, but I believe I will sell it and persue this venture intead. The time needed to finish the sonex kit is more than what I estimate it will take me to complete a SkyRanger variant in total. Have you any experience with anyone using a VW engine on a Skyranger Swift or Nynja? With your wing tanks, will the wings still be foldable? If you have a moment, please look into how they can claim 80lbs of luggage (36kg) on the Cheetah/BushCat? Thank you again!

 

 

[gregrobertson]

Hi Abe.

 

I can't find a lot of information on the Bush Cat but it doesn't look that much different from the Cheetah. Different gear legs and cowls but the wing and fuse look much the same. I don't know about the 81lb baggage allowance but with the Skyranger and Nynja when the fuel transferred to wing tanks it relieves 80kg from the baggage area right behind the seats. Conceivably we could use a lot of that weight for baggage and could certainly accommodate 81 lbs. We would still be bound by our 540 kg MTOW and C of G envelope but 81 lbs (37 kg) would fit in the C of G envelope. The wing tanks (remember they are still very much prototype at present) would not be compatible with the wing fold kit.

 

The Skyranger is available with engine mounts for the VW engine. I believe there is some alteration to the engine cowls required as the VW engine is much wider than the Rotax 912 series. It is also quite a bit heavier. The BMW motorcycle engine is another interesting conversion, I have one client fitting the BMW engine into a Skyranger at present. I believe it fits onto the Rotax 912 engine mount and is good for at least 100 hp. He is in the very early stages of the conversion so I don't have any details at present.

 

I hope this information is helpful.

 

Greg.

 

 

[revlis240]

Greg

 

As always thanks for the replies. A few more for you..

 

Can it actually be built in about 300 hours?

 

The xlam parked outside for years.. How long is it expected to last?

 

With 80hp, can one expect a cruise of 90kts or that more of a 100hp thing in the nynja?

 

 

[gregrobertson]

Average build time for a Skyranger or Nynja is about 350 hours. It depends a bit on how much time you can put in at any one time. If you can only spend half an hour at a time it will take a bit longer as you always have to go back to pick up where you left off before.

 

I wouldn't recommend that you left any aircraft outside for years. All of them will suffer in various ways. Looked after the X-lam should last 20 years but that would be hangered.

 

A Nynja with 80 hp will cruise at close to 90 knots, a Skyranger swift at about 80 knots.

 

Greg.

 

 

[Geoff13]

Greg would the Swift or the Nynja be able to carry 2 * 100kg pax and full fuel. Reading what you said earlier that would stuff op the CofG.

 

Can you fit the 100hp Rotax and does it give much difference to the cruise.

 

Cheers Geoff

 

 

[gregrobertson]

Hi Geoff.

 

The Nynja has an empty weight of around 280-290 kg and a MTOW of 540 kg giving us 250-260 KG useful load. Two 100 kg people and 71 lts of fuel. That would still be inside the C of G envelope. The new wing tanks would bring the C of G further forward with that load.

 

All the Australian Nynjas run the 100 hp Rotax. There is little difference between the price of the 80 Hp and the 100Hp engines so it is an easy decision to make. Most of the Nynjas used in flying schools in Europe opt for the 80 hp engine as it is a little cheaper to run and a better option for training.

 

A Nynja with 100Hp will cruise at around 95 knots, the 80 Hp engine will give you about 90 kts.

 

The Swift is a similar weight but is about 5 kts slower, but cheaper.

 

Hope this helps. Give me a call on 0418 585 731 if you like.

 

Greg.

 

 

[ave8rr]

Bushcat specs from NZ agent website: http://bushcataviation.com/BushCatSpecs.pdf

 

 

[Guest Andys@coffs]

.........when the fuel transferred to wing tanks it relieves 80kg from the baggage area right behind the seats. Conceivably we could use a lot of that weight for baggage and could certainly accommodate 81 lbs. We would still be bound by our 540 kg MTOW and C of G envelope but 81 lbs (37 kg) would fit in the C of G envelope...........

Greg

 

Help me here, I don't understand what your saying, if you move the fuel from the fuselage to the wings, you may well affect CoG calcs etc but in terms of the delta between empty weight and MToW you wont have changed anything, possibly made it worse because 2 tanks will likely be heavier than 1 tank.

 

So again how does this increase the luggage carrying capacity? with the presumption that empty + fuel +people all remain the same?

 

Or have I misunderstood you?

 

Andy

 

 

[revlis240]

That is a good question Andy, I am also curious.

 

If I understand correctly, the standard Nynja kit (including the one in the USA?) comes with a 16 gallon tank and the 23 gallon aluminum tank is an upgrade. The question also is how much does this tank add to the empty weight as I have read it is a little heavy. Also, what is the cost for the tank?

 

I read the Nynja made major changes to the fueling issue that the SkyRanger people complained about. I assume there is some kind of zipper to allow access to the tank?

 

Lastly, is the 540KG MTOW some sort of regulation requirement over there? In the US, the limit is 1320LB for LSA = 599kg. Can the airframe theoretically handle it..or...?

 

Greg, do you have any pics of the baggage/fuel tank area?

 

 

[gregrobertson]

Hi Andy. The wing tanks will not make any difference to our MTOW. or the useable weight. It will make room available for luggage behind the seats which will only be of much use with a lightish passenger. Hopefully the aircraft will be a bit quicker when it is fully loaded as it will not be as tail heavy. I am not an engineer, but the mods are being done in collaboration with Phil Prevot the designer. Evidently it is a good thing to get the weight out of the fuselage and into the wings. In Europe they are happy with the standard 60 litres capacity. As we know 60 litres is simply not enough for Australia. They (the Europeans) simply do not understand how big this country is. I sent Phil a map of Australia superimposed over a map of Europe, he thinks it is a practical joke.

 

Revlis240 The original tanks in the Skyranger were filled from inside the cabin, and to be honest it was a PIA. and not enough capacity for Australia. We had a 90 litre aluminium tank made to replace the plastic standard tanks. This is filled from an external filler point, much easier. The wing tanks are simply a further evolution for the aircraft. Both Phil Prevot and I are always looking at ways to improve the product. Hopefully it will be an improvement. At the moment they are very much prototype. The Aluminium tank weighs in at around 7kg although the earlier tanks (made out of 2.5mm plate) weigh a massive 14 kg. The wing tanks should come in at between 9-10 kg (two tanks) so some will win and some will loose. I don't seem to have a pic of the tank at present which is a little strange, I'll see what I can find.

 

Greg.

 

 

[revlis240]

Greg,

 

Thanks for the info. Some pictures of how the tank is filled, as well as the available baggage area would be great. I have seen the tank, but now how it effects or results in the total baggage area. Since it is likely that I wont ever see a nynja in person unless I decide to build one, I may need more of such pictures if that is okay! :)

 

 

[Garfly]

Here are some pics of the 90L (24 US gal.) installed in my Swift last year by the previous owner.

 

It's the more recent and lighter aluminium tank referred to by Greg (in #12 above).

 

You can see that the luggage bag can still hang above it.

 

But you can also see that under certain load configs you could run out of rear CG before you run out of MTOW.

 

It's in that light that I understood Greg's suggestion that wing-tanks might mean you're able to haul more luggage (apart from having more space for it).

 

I have seen pictures of European installations where the filler cap exits the side wall which may be more convenient still.

 

I wonder how the filler caps will be set up for the wing tanks. It's certainly a fascinating development.

 

 

 

 

 

 

[Garfly]

Here is a video from Germany of that Swift build which incorporates the the side fuel-filler (into the two plastic tanks).

 

If you watch the vid you'll see that this one has the ballistic recovery parachute (mandatory in parts of Europe) taking up half the space the full-size luggage bag uses. (The rocket aims upwards and fires through the flap of fabric above the parachute.)

 

Which points to another advantage of the wing tanks, I guess - you can have your 'chute and baggage too.

 

 

 

 

 

 

 

 

 

[gregrobertson]

Thanks for the pics Gary. I will take some before and after pics of the Nynja fuel tanks and post them here when the wing tanks are fitted.

 

Greg.

 

 

[Jiefuster]

Anyone fitted higher backed seats?

 

 

[Kyle Communications]

wow this is a old thread revived

 

 

[Blueadventures]

Anyone fitted higher backed seats?

Hi I have the moulded fibre glass seats in the Nynja and they are comfortable. Longest flight 4.25 hours to date. They have a padded seat cover on them. You cab see the height of the back in the image. There will be more images on the BestOff sites. Cheers

 

 

 

[Garfly]

Here are a couple more glimpses of your Ninja seats, Mike. (Though taken to show bits of your header-tank/wing-tank arrangement ;-)

 

 

And these are the standard old Skyranger seats.

 

 

 

 

[Jiefuster]

Here are a couple more glimpses of your Ninja seats, Mike. (Though taken to show bits of your header-tank/wing-tank arrangement ;-)

[ATTACH=full]53214[/ATTACH] [ATTACH=full]53215[/ATTACH]

 

And these are the standard old Skyranger seats.

 

[ATTACH=full]53216[/ATTACH]

[Jiefuster]

Here are a couple more glimpses of your Ninja seats, Mike. (Though taken to show bits of your header-tank/wing-tank arrangement ;-)

[ATTACH=full]53214[/ATTACH] [ATTACH=full]53215[/ATTACH]

 

And these are the standard old Skyranger seats.

 

[ATTACH=full]53216[/ATTACH]

Can you buy the old skyranger seats at all?

 

 

[Jiefuster]

I notice on older Skyrangers some have a thermal blanket behind the seats to allow cabin heat to be more effective. Does anyone know if this is available for the Nynja?

 

 

[Garfly]

You could make enquiries on these sites:

 

bestoffaircraft

 

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