Red

I'm not sure why people build these things , its not advancing anything its just buying some existing tech and ending up with an aeroplane that doesnt do what it did before you ripped the engine out.

What am I not getting?

The short clip of the model on the treadmill at first glance will convince some, look closely and you will notice that she holds the model for a short time so that energy is put into the system and on releasing it drives the model, basicly the treadmill is spinning up the wheels while she inputs a force to keep the model stationary instead of it reacting and moving backwards, the whole description is cleverly tthought out and explained, but its a joke

On 24/08/2021 at 4:25 AM, facthunter said:

It's not perpetual motion though when you get and use  energy from some thing in an efficient way.. Nev

You can't get more than 100% efficiency in any energy conversion, this device is a joke cleverly explained

On 24/08/2021 at 3:52 PM, onetrack said:

The wheels are actually driving the propellor via leverage, the wind is not driving the propellor. The propellor is pushing the vehicle forward, against the tailwind. There are multiple factors at work here, propellor efficiency being just one of them.

 

Put simply, the car is leveraging the available energy from the tailwind, to travel faster than the wind speed.

 

https://docs.google.com/document/preview?id=10qzwC8BmR3fr-ezvSveZ1cOJxZ_4gObOk3DHHaPp2GY

Sorry to be blunt, but taken as read that is complete nonsense

P.S. Just read the attached file ..good grief does that guy  sell Dihydrogen Monoxide

Apparently Captain Kirk is going up next....To boldly go where no 90 year old has gone before🙂

Quote

the main gear is too far back, meaning that when landing with a load of fuel in the front tank it is quite difficult to flare sufficiently to have the main gear touch first, with the result that the noseleg tends to be placed under undue strain with disastrous results.

Might want to think that through Microman

On 26/07/2021 at 1:25 AM, Bruce Tuncks said:

My suggestion would be to apply proof-loads before flying.

 

Now I've heard some silly things but...

3 hours ago, coljones said:

Tweed might not be a mathematical term but it is an engineering term.

Blimey is it?, I thought it was a type of material used to make jackets out of 🤪

On 26/12/2020 at 10:33 AM, APenNameAndThatA said:

The thing about flying is the sheer physicality of it, and the high stakes. IMHO riding a bicycle is a better simulation of flying than Flight Simulator is. 

I thoroughly agree

I've been reading Internet forums for a loooooooooong time (probably too long and I think I can honestly say I've never seen anyone dig such a big hole for themselves....astounding

Its really pretty, but the flight model for the prop singles is not great in some aspects, Landing the taildraggers is way too easy you have to try hard to mess up, you can climb at <Vx with no rudder needed to keep the ball centered and on the take-off roll the slightest crosswind from the right (2-3 knots) will completely overcome the tendency of the included taildraggers to swing left on raising the tail and swing you the opposite way as if the crosswind was 10+ knots..... very unrealistic

Turbulence seems well modelled

Its multiplayer function is awesome

Overall X-Plane has more realistic flight dynamics but MSFS 2020 is a fantastic game and great way of explorinng places you know or have never been to.

Has been great fun when stuck home

Agree on the lack of tech pieces in UK Mags and far too much emphasis on personal stories of some awesome trip which generally have the same effect on me as people showing their holiday snaps and describing how great the service was at the Tapas Bar.

Saying that, the last Flyer mag had some good stuff

Should I close the Jab Engines group?, it seems to be superflous with 99% of activity in this thread.

Probably better to keep all the info in one place....what you think?

Hello Bruce,

I'm a newcomer to Jabs, but have a lot of time on Rotax 912 which uses same carbs

I tend to view Hoses as an 'on condition' component carb overhaul for the bings If I havn't touched them in 5 years then I will take apart and replace anything needed )Diaphragms I change regardless of how they look).

Carb Socket I will also change if it has lasted 5 years (in my experience some can go bad much sooner)

I use only Ethanol free fuel, if using fuel with Ethanol id be looking very regularly at my hoses and carb floats

Jabiru Fuel pump is a bit of an unknown to me right now

Such a shame these projects ended up in the hands of Walter Mitty

Flightrite I am running Iridium plugs in a 2200.

I fitted them as I was changing to resistor plugs to tackle some interference and decided to use Iridium resistor plugs to counter possible harder starting due to extra resistance

They seem to be performing well with easy starts

I use Yuasa Batteries on my microlights and motorcycles, they don't claim wonders but they do what it says on the tin and are realisticly priced, never had a duff one

not surprising really given their experience at making the things

Can't find anything about the LAA Jab course, got a Link or other reference mate?, Id be interested in attending.

I believe they are structural stiffeners above the wheel wells fitted after the wings on some early mark 5s rippled in that area under +G and it was later replaced with thicker skins in the area

P.S. Spitfire wing types could probably fill a book, there where loads of variants

PPS.......Emu do you by any chance deal with aftermarket truck bits?

Brinky, I have similar safety straps on my bungee gear and also they seem completely inadequate...in fact

http://www.lightaircraftassociation.co.uk/2015/Magazine/Oct/safety_spot.pdf

though tbh the strap does seem heavier gauge than the one in the OP

"I've read that Rotax carbs are not clamped to their rubbers so that they are dislodged by wild engine vibrations, automatically cutting off their fuel. "

Koreelah, Rotax Carbs fit to their boots exactly the same as a jab carb, if it had no clamp it would get thrown off every start

they do get thrown off sometimes, I've had it happen, but that is only because of the very violent shakes they sometimes exhibit with bad starts on a cold unbalanced engine installation with no airbox supporting the intake end of the carb as in Skyrangers etc

You’re right on the money there. You can pretty much decide whether a fuel is viable by looking at its law per cubic metre performance for vehicles or aircraft. In this case a lot more cubic metres has to be burned for about 15% less power than ICE. The golden era so far for this gas was the late 1980s. The transport industry solved the volume problem by compressing it to 2000 psi and making huge tanks from fibreglass rovings and resin. In that era for some reason people didn’t like calling gases by their real name in the transport industry and it was called CNG, Compressed Natiral Gas. The tanks would be too big and heavy for aircraft. Benders Buslines in Geelong had 105 buses on CNG. All the truck trials failed and Benders reverted to diesel.Within 10 years it was all over. Currently works in gas-fires power stations.

Same problem with Hydrogen, the tanks would have to be huge and heavy, not viable for aircraft

Too short

Thread Moved

Nobody in here for a while so I'll just give that last thing an ID via Google:

Sigma 5

Nice looking thing, but I remain hugely sceptical about so called flying cars.

Have a go at this: