kasper

Doors of size “x” when you need “x+” is not a design fault. It’s a procurement failure on the part of the Australian military and/or govt. if the manufacturer said they could/would redesign to “x+” and they didn’t then that’s also a procurement contracting failure - we failed to make sure it is + general serviceability is always an issue for military hardware. It’s expensive to buy. Expensive to maintain. But has to be available. If the airframe was unable to meet serviceability levels with specified usage AND that was in the procurement process then manufacturer might be responsible. But if it’s not it’s on us. now if the real reason is that a slightly smaller capacity more robustly built machine that our military has decades of experience with is easier to change to and achieve the serviceability and availablity requirements then continue with them then the decision to scrap early and replace is probably the right decision

Wing radiators/surface radiators were used on the Supermarine S5 with the lion engine from napier From memory Corrugated upper surface radiators for the engine coolant were built onto the wooden wing Corrugated surface radiators for the oil were on the rear fuselage sides aft of the cockpit Fuel tankage was in one of the floats - and that float was offset from the centreline by a different distance than the non-fuel filled float The S6/6B used Rolls Royce R engines (the basis for the merlin) and added more surface radiators for engine cooling on the floats as well as the wings ... also think they extended the oil radiators on the sides forward of the cockpit A quick google will probably prove my memory faulty but that wat I 'member

If that's me I can only add a little as I only looked after 1 drifter and spoke to Wayne F on what to look for and care for when he delivered it remanufactured/overhauled to this back in the 90s The maxair and austflight drifters do not have a weakness as such at the engine mount to fuse tube BUT that is a stress point AND a corrosion point. The folded metal floor is rivetted to the fuse tube along the tube length and Wayne was clear that the thing to watch was any streaking from a fretting rivet from stressing in that area. That was the point where you needed to unrivet the sides to inspect the tube for stress cracking which you couldn't see with the sides on. From Wayne the issue was that once a rivet started fretting it was a moisture trap for corrosion in an are where cracks from rivet holes were at a high stress point along the tube. Never had to strip one down because there was never a need whilst I was working on the maintenance or instructing in it.

I’ll just stick with cruise at 55% power on a fixed pitch prop that at sea level is properly set up to absorb that power at that throttle setting and has WOT that is exactly per the graph. and anyone who thinks the minimum/proper cruise power setting is well over 75% can have the fun of finding out all the bits of the engine that need work when run at high power. I’ll just keep plodding along on a half hours engine that exceeded its years life nearly twice but issued bugger all oil and has compressions that are unchanged in the last 200hrs and 10 yrs.

I can’t say thousands as I’m only a weekend flyer. The engines in all the raven 912 eclipsR trikes have performed perfectly for the past 20 years and there is no history of issues. Only know that because I worked at the factory building them for years and flying them as an owner. we set that engine / prop combo up and it works. As for overpower I’ll agree. But you tell me what 50hp 4 stroke engine was available 20 years ago that would sell to the market? There wasn’t and the market was anti-2 stroke so there was and remains no option except the 912.

I would BUT for the fact it’s a trike and it’s been propped to that power setting. 4300 by the book burns 11lph when the power is fully absorbed. The aircraft burns 11lph when cruising at 4300. The prop is correctly set for the rpm. thw result is that it’s burning the correct mix and it’s ok. The 912 in this airframe goes for hundreds of hours and never misses a beat. The only failure I’ve had on the engine was a failure of 1 ignition unit - and that was found with ign check at 3000 😛 if your engine is burning the correct fuel for the rpm your prop is set to the correct cruise. on the raven you simply can’t run 5200+ because the airframe is coming out of the top side of the drag bucket above 4300 … all it does is make you exhausted holding the bar or make you climb at many hundreds of fpm. Cruise climb at 4600 gives over 500fpm at mtow … I’m not going to run it any where near 5200

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.

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.

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.

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

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.

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?

"a single 180 horsepower Lycoming HIO 360 is enough to get the helicopter and both occupants airborne" That makes me laugh ... ONLY 180hp to get two people into the sky ... types the guy with a two seater R447 ultralight that manages to get two people up there on 40hp. All noise and thrashing themselves those helicopters 😛

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.

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. $$$$$$

Nev, Wood and fabric may be old fashioned skills BUT they are materials that are better suited to repair than composites and easier than metal... and potentially more 'green' than the fashionable composites. This coming from a middle aged fart who has built and played in all construction methods and I am trending back towards wood and fabric for my last two aircraft and looking at replacing the composite wing on one of mine with replacement in wood n fabric.

No - the dates are correct. John was a skilled and busy chap ... but with a job at technical college that allowed him freedom to build. He had built a Curry Wot previously and the Fury structure is based on the Wot. When it came to his Spitfire it took him longer as it is a much more substantial and complex airframe.

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.

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.