J170c - The Bee's Knees

[BigPete]

Huge aviation event in Echucan this weekend;)

 

Saturday - AAAA Fly In - so many wonderful old aeroplanes to look at - will post pics later.

 

Sunday - Airshow - will be great.

 

However - the reason for this post.

 

I had the pleasure of flying Cliff Banks new Jabiru J170c yesterday.

 

What an incredible difference an extra 1.4 metres of wingspan can do!! (and the 230's elevator)

 

Lift of at 50 knots, climb like an eagle at 62 knots (two people and around half fuel) and TROLL.

 

It's the best way to describe going S L O W - 2000 rpm - half flap, nose up and we maintained height easlily while walking along at 42/43 knots just above stall.

 

It was beautiful - almost helicopter like - another world. This aeroplane wants to fly - takes longer to build up speed and has a slower roll rate, but who cares?

 

With the wing loading on the J160c the aeroplane needs speed/power to support the weight. The J170c has buoyancy. (It floats).

 

Anyone out there want to buy some slightly used 160 wings??;)

 

regards

 

 

[BigPete]

Hi Chris

 

The 170 has the same cruise as the 160.

 

Echuca airport is on the road to Kyabram, about 4 km out of town - you can't miss it - look for a big open area with lots of aeroplanes on it!

 

 

[Yenn]

The downside of the bigger wings is that turbulence will feel much worse. At Rodds Bay it can be a bit turbulent at times and some pilots prefer to stay on the ground then, whereas with a bit higher wing loading it is possible to travel in comfort, and also float can be less when landing.

 

 

[Guest brentc]

I don't know how they can make the J170 cruise the same speed as the J160. It has up to around 5ft more wing and wing tips causing drag. The J230 cruises around 6-7 knots slower than the J200 in general. The 2 new J160's when brought down to Tooradin from Bundaberg and were cruising at 2,950 rpm on 110 knots. From what I understand the J170 isn't achieving that. Short wings are for speed and sportiness and the longer wing for higher loads, shorter takeoff and landing and a bumpy ride.

 

 

[BigPete]

Ok - let me clarify

 

I understood the cruise speed of the 160 to be 100 knots at 3050 rpm.

 

I've been told the 170 also cruises at 100/3050 rpm.

 

The theory is as the 170 has more lift due to the wider wing, more power is converted to forward speed - does this seem reasonable? I must confess I'm no expert.

 

If my 160 could do 110 knots at 2950 - I'd be overjoyed!!!

 

regards

 

 

[Guest J430]

Brentc speeks the truth.

 

His J400 (short wing) Vs my J430 long wing......5-7 knots......FACT

 

Can't have both I am afraid, if you could.....I would:keen:

 

J;)

 

 

[Captain]

Can't have both I am afraid, if you could.....I would

J

 

You could have both .......... but it would take a little effort to make it fly straight and level.

 

The J160 that I have flown doesn't "Cruise" at 110 knots. I reckon that it takes more than true/real world cruise power settings to get that speed.

 

Regards G

 

 

[Guest Ken deVos]

Perhaps you will need 'both hands on the stick' to achieve the quoted speed, but note that the speed and 40/45knt stall figures are for a 600kg MTOW rather than 540kg and 45/49knt of the J160C.

 

Quite impressive for the 85HP engine and assume the more glider-like wing aspect ratio produces lift more efficiently.

 

 

[Guest brentc]

Ken are you saying the J170 has a different aspect ratio? The J230 - J200 difference is merely 5 ft of length total plus wing-tips.

 

 

[Guest Ken deVos]

Brent, just quoting from the current Jabiru Co. specs and specifically comparing the J160C with the J170C, then the wing aspect ratio of the latter is 19.5% higher.

 

Interestingly, the J170 kit a/c has shorter wings and a lower aspect ratio than the certified model but still higher than the J160C.

 

All these a/c share the same 990.6mm wing cord dimension.

 

 

[Guest brentc]

Knowing them, probably an error on the web page or something. Seems unlikely that the kit would be different to the certified model, but you never know.

 

 

[Guest jabgrl]

Yeah I agree with Brent C, so unlikely