kasper

Well my need to check at 3,000 is aircraft specific ... but is not uncommon for 912 trikes.

1. the same wing I have a rotax 912 on - Raven wing on an EclipsR trike - flies two people on a Rotax 447 with only 40 HP - Raven wing on a RavenX trike 

2. the 912 is putting out 46hp at 3,000rpm so its brake system is working pretty well to hold just that ignition check rpm

3. the 912 at 4,000rpm is putting out over 55hp ... there is not enough rubber on the ground to hold it 

... not surprising given the cruise power setting for the 912 on the trike is only 4,300rpm.

2 hours ago, Methusala said:

Thrusters have never had doors.

Ummm.  Yes some do.  
T500’s most had doors - front hinge

T300’s could have them - front hinge
TST/Geminis are not supposed to have them (or the rear cabin bulkhead)

At least two single seaters had had enclosures including doors added - front and top/bottom hinge.  

7 minutes ago, skippydiesel said:

As per JG3 - I do my Rotax 912 RPM checks at or above 4000 rpm

Agree with 3000rpm as my ignition check setting ... can't do 4000 as that's enough to take off and on wet grass all braked wheels will skid at that much power 😀

Those chinook fuel tanks are rather expensive for what you get - 19l of fuel and the tank is over A$500 plus shipping and GST from the USA.

if I have that sort of cash for a fuel tank I’d go for a seat tank -two items for the price of 1 😛

Focke Wolfe 19 ente or duck in German.  A very Teutonic way to name a canard or duck in French.  

1 hour ago, Geoff_H said:

For some years I have been trying to make an aircraft for less than $10k.  First attempt was scrapped as it was far too heavy.  The idea was to make moulds and loan them out, really not feasible, too easy to damage the moulds.  I am on second attempt now.  Engines $4k, leaves $6k for fuselage etc.  Use phone efis, may work.  Hand held radio.  Probably on target but making many parts in my lathe and milling machine. I expect that I will achieve the end result.  The aircraft is small and I am using quad bike braking system. I machined wheels from single blocks of aluminium.  Canopy will blowv$10 if it is bought, I will have to make it, doubt that the result will be ok.

I have many 3d printed parts.  I have spent $4k on tools, excluding lathe.

I am 74 now, I don't think that I will finish it before I loose my medical.

You might like to reconsider the quad bike discs.  You will find that a flat will have the disc on the ground and it’s likely to twist and jam.  I use Vespa hydraulics on the 912 trike and a plane stainless disc cut to be the diameter of the wheel less 5mm.  From experience a total flat does not cause disc strike and it pulls up 450kg of trike on grass in under 100m

2 hours ago, Thruster88 said:

Just a reminder the thread is about affordable flying. Anyone beat the 6k thruster.😂

Less than $3k for the panther xl trike in 2008.  The the raven xl trike in 2014 was $1200 but I had to overhaul the engine so that one comes in at just over $2k plus my time.  The home built trike has cost just over $6k but that’s all new except engine that was 2nd hand. 

Now how about the medium term outcome of LARGE numbers of electric vehicles ... 

1. most vehicles sit around most of the time even during daylight hours.

2. If most of the vehicles sitting around most of the day have a large battery inside AND you plug that vehicle into the grid

you can pump electricity from solar through the network and store it in a distributive way around the nation

and if those cars are still plugged in at night you can draw back from a distributed network (consumer setting minimum levels of retained battery)

Yes there are larger losses when you keep transforming currency/volts and then distributing and charging ... BUT its a way of adding capacity to the wider network.

I have been having fun at home with old crappy stuff given away when solar system upgrade ... I took 6.25kw of retired solar panels, three 200l electric hotwater systems (from the tip) and paid $140 for three replacement 36v DC elements ... I now have a stand alone system with 600l of hot water that is on the dairy ... no battery as for this system I am storing energy as heat in the water ... but as I NEEDED hot water its actually more efficient.

Bit of thought and things can be done.

I am now eyeing off the rotary hoe to loose its petrol engine ... and the batteries can be low tech as I need the weight on the machine ...

I think the reason it’s not in combat aircraft but has been/is in gliders is the restrictions on overall ability to reposition your body in the cockpit to adjust sight to areas not within your sight in the normal position.  
 

gliders address the limits of reposition with extensive glazing and they towelling hats.  
 

fighters in a seated position have the greatest ability to move their bodies around for max vis options and they seem to accept that gforce management takes a second string to that. 

Northrop xp-79 ram. Rocket motor. Prone pilot. Flying wing. What could go wrong?

crashed.  

On 14/11/2021 at 9:07 AM, Bruce Tuncks said:

I reckon that battery was illegal for sure in a VH plane, but it may also have been illegal in a 19 reg Jabiru. I think the article I had said that the guy had built the plane from a kit. The wife read the article and got angry with me for saying how he caught fire unnecessarily.

Mind you, the quality of the report was poor and there may be misleading bits there. It was obvious to me that the reporter knew nothing about batteries, for example.

How could a battery be illegal on a 19- reg airframe??

The manufacturer of the engine cannot stop you using a battery - its not part of their engine (and you modify that anyway) - and I do not recall any Tech Manual areas that would mean RAAus have anything to say to you ... so how can it possibly be illegal?

5 minutes ago, Bruce Tuncks said:

Weight-shift aircraft operated from Gawler some years ago. They flew at dawn and dusk, making our neighbors upset, because they didn't like the wind and turbulence and thermals of the main day. I am pleased to say that their importer has moved onto expensive but real planes. His real planes only cost about 130,000 but I bet that is not the end of the payout you would be making.

Besides, the weight-shift planes were not that cheap, although I can't give an actual price. But I would bet you could buy a Boomerang ( Schneider wooden glider of 30:1 performance) for about $6000. You could still do a 500k flight in one of these.

You can’t compare old wooden glider second hand price to new weight shift. But a modern 912 weight shift can fly as a real plane.  12-15knt cross wind is possible (not fun) and cruise at the top end is 80knts.  But it comes with the cost.  
 

compare 

first weight shift I bought was second hand and OLD and I paid under $2k to buy and get registered - did 40knts and was fair weather machine.  

second weight shift second hand was an 8yo 912 powered.  Great fun and much more capable but cost me $20k before I upgraded it for full CTA flying in the UK.  The panel cost an additional $10k

a new high performance weight shift would be in excess of $65k starting plus electronics.

show me any factory glider for under $65k available today then there is a comparison to be had. 
 

but until then comparing an old wooden glider to a new weight shift is apples and pears. 

1 hour ago, APenNameAndThatA said:

I keep mentioning this, and nobody agrees or disagrees: isn’t weight-shift the new rag and tube? That is, don’t people who want cheap flying now do weight shift?  

One simple answer - engine availability.  The R912 is the killer of low cost airframes - and its ubiquitous.  They make operating sense to a school with high utilization hours on an airframe but are just MASSIVE sunk costs in an airframe used a few dozen hours a year.  

Slightly extended simple answer - you fly what you are taught in - 2 strokes and low performance airframes are not used in. 

I would gladly go back into instructing if an local school had the airframes I PREFERRED training students on - Drifter 503, T500 thruster and a 582 GT500.   Also I NEVER taught to make money - I did it because it was fun for me and I enjoyed it more than watching sport on TV with a pie on a Saturday.

Logical extension to the simple answer - once you have 25K sitting in the engine you can 'justify' adding 10k for a constant speed prop and then a glass cockpit make sit all look modern ... oh and everyone LOVES speed to it will be composite  ... and to keep within MTOW limits for operating it will be carbon/kevlar not old S glass. $$$$$$

You open a can of questions with answers that are nearly all maybe.

Basic rule - if it came out of a factory it must remain unmodified from that accepted configuration state and you have to maintain it to the manuals for that factory and/or/maybe RAAus Tech manual

This odd and/or/may on the tech manual is because a factory document can override the tech manual and the tech manual can supplement factory docs ... eg if the tech manual says one thing but the factory doc on the same item says do another you HAVE to follow the factory OR get MARAP from RAAus to make Tech manual rule over factory.

Basic rule - Depending on what originating approval/acceptance path the factory build fits within CAO 95.55 you will have a special certificate of airworthiness, or experimental certificate, for the aeroplane and that certificate sets out limits of use.

So factory built that no longer fits factory spec (or modified factory spec er MARAP or CAR35 changes) will get an experimental certificate that many of your questions fall under the individual experimental certificate:

1. can it be used for hire?  maybe - depends on the wording in the certificate 

2. is it in effect a kit - NO - its still factory and you have to remain within the limits of the experimental certificate - you want to make more changes beyond what the certificate was issued for you need to hand in the certificate and get a new one.  Kit/home builts in 95.55 can make as much change as you like and its within Tech Manual for how/what needs to be done in terms of flight tests and inspections

3. can it be L1 maintained - probably - it can unless the experimental certificate says it can't

4. What mods are possible - whatever is agreed for that experimental certificate - they apply to a single airframe with listed non-factory conformity - make more changes need must a new experimental certificate

5. who signs off mods - depends on the experimental certificate and what it says - but that is only for the initial mods that made it experimental - any more after the issue of the experimental certificate and its start again.

1 hour ago, FlyBoy1960 said:

You are forgetting one of the most important things, the slower you are going the longer you are affected by the headwind so you wiil therefore use more fuel than you will going fast because you are affected by the headwind for longer

Yes and no.  The quick table I put through with fixed costs added ($20/hr) takes account of time and fuel burn.  The other way to look at it is to graph the cost per NM travelled over the ground against the headwind for the three power settings to see the difference:

As can be seen up to around 20 knts headwind power is making bugger all different to $/nm but after 20 knts the low power setting becomes quite a lot more expensive.

But again ... who wants to be flying for 'fun' in more than 20knts of wind?

Plus its generally a plannable distance vs headwind that is more the problem for ultralights ... with a fixed fuel available of 90L in a foxbat the real importance is how far you can get on your endurance ... lets leave 9L for reserve and look at 81L ...

This shows that lowest power will give you longest plannable range for all headwinds up to 25knts  ... but who wants to be doing that as you are up there for longer to get there and I really prefer to run my engines in a higher cruise power setting as temps stay nicer and I have a better flight ... my bladder will not hold out comfortably for 5hrs to go 400nm at 85 let alone 5hr20 to do the same at 75 ... with more than 40L in the tank I am really looking at how many legs in total before I have to refuel on tankage and just fly legs that suit my need for fun and my requirement to be comfortable between hamburgers and toilet stops.

If you like I have pushed your fixed data through my planning sheet based on what you have.  I plan only 100hrls and engine replacement and I have guessed the cost of a 912i

nil wind = 4600rpm wins on cost/nm just over the 4000rpm

30kn headwind = 4600rpm wins on cost just over the 5000rpm

Were this me I all I do is ignore the $/nm and work from cruise power setting and work out if I can get there with planned winds and available fuel.

For example,

My 912 trike has a std 80hp 912 and is drag limited so I am only able to run 4,300rpm and get 11lph for 60knts - any more revs and I see rapidly declining return in speed for the fuel due to drag.

So I am always looking at my distance based on 3.5hrs fuel (plus reserve) in the two seat configuration which limits me to 210nm still air planned if I take a passenger

Any more and I have to ditch the passenger and install 'George' the fuel tank in the rear seat ... adds 6hrs to my fuel so I can then plan up to 570nm still air.

2 hours ago, spacesailor said:

IF we havn,t got a 103 type  !,

HOW IS, that ' nano ' kite flying ?, No rego & HE said, " no licence ", 

No registration means Raa can,t ' find ' him,

YES, first hand account.

spacesailor

Powered hangliders are under 70kg and not registered a aircraft etc but use is subject to SAFA - the new hgfa - see CAO95.8

10 hours ago, jackc said:

A personal friend of mine in the U.S. has ordered one with a Hirth 23 engine, there is a 12 month wait.  I checked with RAAus and they on the approved kit list here and can be done under 19 rego,  not sure on the electric model.

I got all the pricing on one and naturally more expensive than the 2 stroke powered ones. Can choose Hirth, Polini or MZ engines, naturally no more Rotax.

They generally fly in the U.S. under the FAR Part 103 regime, no rego, no licence needed.  Sure wish we had that category in Australia.   A low budget entry point for Foundation Aviation.  Australia is too dumb for something like that 🙂 

Whilst I really have a beef with the costs and direction of raaus I lived through the wild days of no-licence ultralights in OZ and the outcomes that resulted.  Training is a need. Full stop. 
 

the areas that I am concerned with are the control of ops.  The choices are the likes of CASA or an industry group.  
 

we have muddled along with AUF and RAAus for over 30 years as the training and control body and whilst they have been problematic - esp in terms of advocating for and change and enforcing control on behalf of CASA - it’s a tension but the training and certificate requirements in OZ have been largely effective

Still brings a smile to my face to remember the T300 I first went for a TIF in back in Dec 1986 over in SA ... blood ran a bit cold when the instructor nearly fell into the prop when pull starting the 503 with me strapped in ... but after we were in the air the Thruster was and remains the bees knees of Australian ultralights ... Drifters are fun and the Lightwing is comfy but the Thruster had my heart from that day.

Hmmm

From the T300 I used to fly, the T500 I owned and the T600s in the UK I used to fly I am at a loss to understand the problem unless you cannot lift your arm and look back at the sight tube through the cutout in the centre of the cabin back.

In all of the Thruster two seaters I owned/flew there is a clear Perspex insert in the rear of the cabin through which I could see the sight tube that ran up the centre of the tank.  On mine I marked the ground attitude fuel on one side and inflight levels on the other ... and marked them Ground and Flight.

All I needed to do was lift my arm and look back under the armpit to see the fuel state.  Always ran a fuel log on the flight plans but used the sight tube to confirm/amend actual to plan as required.

Quite important in the T600's when you are flying around the UK and into/out of military airspace as you often got held or flown around the houses to get around them so fuel planning became more critical.

Here in OZ the majority of my Thruster flying was just local pootling around for an hour or so without any plans other than to go have some fun so I just ran from full tank and refilled to full after each flight.

On 17/08/2021 at 3:10 PM, skippydiesel said:

I have experienced truly violent turbulence in the vicinity of Katoomba - still shaking when I got back on the ground at The Oaks. I now approach that area, ready to reduce power at the slightest hint of vertical air movement.

 

On the other hand - years ago, when returning from Cowra to Condobolin, in a C172, I had entered a very smooth (no violent movement)  powerful updraft that had the aircraft climbing at idle power, at at least 1000 ft /min. Seconds later entered the down draft, unable to maintain altitude at full power. At no time was I as terrified as the later encounter over Katoomba.

Might explain my preferred route Cowra-The Oaks being via Goulburn and Mittagong 👍.   Never been over Katoomba in a aircraft I was responsible for flying. 
 

my worst was in a weight shift crossing the Loire valley heading into Chartres. Neg G is a no-no in them but I went there many times that day.  Got on the ground and lay on The grass for half an hour next to the plane. 

41 minutes ago, facthunter said:

Belts are an "easier" drive where torsional pulses are present. Flat twin 2 strokes would have to  fire together. The only one I know of was a Victa and they are awful. Nev

Kfm 107

Hirth f23 

Wae 342

I have all of these with and without belt redrive and all are lovely to run at power. The WAE are direct drive only and are rough and rock at idle but all with redrive are fine even at idle. 

16 minutes ago, facthunter said:

You have to make a VERY idiot proof engine as idiots are really good at mucking up idiot proof engines. They use great ingenuity to do this.

   Make it SIMPLE and it will only go together one obvious way. Flat twins shake too much. Both pistons STOP twice per turn and that really plays up with the flywheel effect. Usually the prop is the only flywheel it has. Nev

Which is why flat twins of the two stroke cycle work better with belt redrive than a gearbox.

I have a good 38yo flat twin giving 28hp that runs nicely and gets new belts every 100 hrs.

My 50hp belt drive flat twin is only 10 hrs in use but equally runs nicely and I'll keep an eye on it over the next 50+ hrs to see how it plays out. 

The 22hp Direct drive twins I have are ex drone and are short life engines spinning only 38" props but the three I've flown have been as expected.

I don't think flat twin 2strokes are a problem

Dmotor want to deal with OEM only or sell a full install kit to you or fit the engine themselves.  I guess they know  the best way to get a bad repnis to have random installs that cause problems and get bad word of mouth. 
 

verner were lovely.  But they discontinued all radials under 85hp so they are not single seat options.

other radials exist of course like the Australian one in development.   And that says it all really. In development is  99 out of 100 times shorthand for never sees the light of day. 

Jack - Any Hummel build from any set of drawings or plans or parts kits are perfectly acceptable to raaus and just need to be registered under 95.55 not 95.10.  They will get 19- reg and it’s a straight forward process. 
 

spacey has a 23yo grudge against how he was treated in his Hummel when he was going under 95.10. I have offered for no charge to help spacey get his airframe registered under 95.55 if he wants.  
 

this offer stands to him as it has for the past 4 years.