F10

A point of conversation. Most engine failures I have heard about, are the result of a bad servicing or servicing error, or incorrect operation by the pilot. It is rare that a healthy engine that has been running for a while, will suddenly fail.

Yes. Unless I read it wrong, it talks about monitoring engine parameters form at every annual and said form attached to the maintenance log, to run on condition. I saw no mention of an annual MARAP submission for $330.

Yes the MARAP allows for modifications as in the Gazelles case. That's not the issue. In fact the MARAP is a fair system, and allows for changes to a certified aircraft. According to what I was told, if I wanted to fit a 100Hp 912 to the Gazelle, I could do that through the MARAP system. Cruise speed would probably not change much but ROC would be improved. The issue here is the annual renewal cost. I think that is a rort. I have no problem paying a fee for MARAP approval, but it should be a once off. We pay enough with membership and rego fees.

This started when I had tried to do the right thing by putting in a Modification Approval Request Application MARAP form to RAAus to fit a new Bolly prop to my Skyfox Gazelle despite the aircraft having had one for years and despite one if not two previous condition reports stating it had a Bolly prop. So after $$$ for that, I was also advised to put in a MARAP on my engine, because it was running on condition. Looking at the RAAus tech regs, as I understand it, it says running on condition requires the usual bleed down compression checks, oil filter element checks and monitoring for any unusual temps and pressure changes. It says the on condition form should be filled in and attached to the maintenance log. So, no probs and it was the last I heard of it. Since then I have done two annuals and re-newed the rego'. No mention or query on the engine condition MARAP. I have now sadly sold my Gazelle. A condition report was submitted. The new owner phoned a few weeks later me as to both himself and myself, he has been told by RAAus that his permit to fly is being withheld because his engine on condition "MARAP" has expired, and he needs to submit one noe EVERY YEAR....for cost of $330......!! So lets sum it up. Ever increasing membership costs, aircraft rego costs and now, all members running engines on condition....an additional $330.....so you are in for around $700 in just admin costs. Now the other issue is the unfairness. Because many engines are being run on condition and are not on the so called "MARAP Register". The Gazelle has come onto the radar, because it was sold. Needless to say....CASA has perpetual registration and NO COSTS to an engine running on condition. If this is RAAus encouraging aviation, then they have lost me. I have sold Gazelle because the now compulsory two year pitot static check, all the above mentioned costs and hangar fees (nothing to do with RAAus) and the fact that suddenly Recreational aircraft had their immunity from landing fees in Gippsland withdrawn, (to silence from RAAus, AOPA I think tried or will try to address this) had me looking at around $3500 in essentially admin costs, before I have even got her out the hangar....... So after around 30 years in the game and 6500Hrs in military and civil flying....I have bought myself a CFMoto 800MT and am enjoying the motorcycle very much. Costs...once a year rego of $550. So, bottom line, I think the annual engine on condition MARAP charge is a money grab, and not in the spirit of promoting recreational aviation.

Yes Machii jets had low melting point (lead I think) plugs in the wheel rims, so overheating brakes would cause tyres to deflate, (melted plugs) rather than the tyre to melt/explode, far more dangerous. Aquaplaning in the Machii was unpleasant as you would use differential braking to steer, when rudder effectiveness had dropped off. But that would take some pretty deep water on the runway. There was a Utube clip of some interesting experiments done by NASA, running a Boeing 737 nose gear, in a concrete trough with different speeds and water depths. once up and aquaplaning, the wheel actually comes to a complete stop, as shown by the high speed camera. This leads to the water under the tyre turning to steam and burning the tyre. The Lear jet used engine bleed air to rotate the front wheel, as a still standing wheel would generate a bigger splash touching down, sending water right into the engine intakes. Some nose wheel tyres will have a ridge on the tyre wall, to deflect water. In Oman I noticed the Hawks would thump it down on the runway, a carrier type landings. I asked, and was told a soft gradual touchdown leading to lots of impressive looking smoke and drama as the wheel spun up, greatly increased their tyre wear. Made sense.

Yes! In addition, what is the effect of load factor? In a level 60 deg AoB steep turn, you need to hold 2g. To see the load factor effect, take the square root of your 2g load factor (1.4) and multiply 50 Kts Vref by 1.4, that gives you 70 Kts!! So wanging around in tight orbits…better bump up the safety speed! This is an exponential effect. A 4g turn will double your aircraft’s stall speed.

These are Bing constant velocity carbs, opening the throttle butterfly will cause the slides to rise up, withdrawing the needle from the diffuser, letting more fuel into the venturi. Are the slides moving freely? Nev correct, the rubber diaphragms in the dashpots could be leaking slightly. If the slides don't rise up, you will have a short term leaning of the mixture. Consider cleaning carbs and renew needles and rubber diaphragms. Private message me, I can give you the contact details for two members of the Yarram Aero Club, who know a lot about Rotax 912 UL engines and Rotax engine tuning. Enjoy your Gazelle! I have one and have had an absolute ball flying mine! A fun and viceless little aircraft. And before we see posts making you feel less of a pilot, because of their claim that the Gazelle is soooo easy to fly it's almost not an aeroplane....like the famous and beloved Piper Cub, about which it is said "A Cub can almost kill you"....so too, disrespect it and the Gazelle (like any aircraft) can hurt you, badly.

Yes true, aerobatics below 500Ft its no mans land, no matter how good you are. But if you are calling stalling exercises aerobatics, think again.

Thought this post was after the quoted one, but no, so this re-posting it. Well hell yes, however over 800 hours on Harvards in the military and countless stalls powering/off, g-stalls, incipient and full spin recoveries plus extensive aerobatics, and in a Skyfox Gazelle @ a MAUW of 520Kg’s, made me comfortable at 2000Ft agl. But yes, always stick to your comfort zone.

Well yes, however over 800 hours on Harvards in the military and countless stalls powering/off, g-stalls, incipient and full spin recoveries plus extensive aerobatics, and in a Skyfox Gazelle @ a MAUW of 520Kg’s, made me comfortable at 2000Ft agl. But yes, always stick to your comfort zone.

Yes agree, 85 Kts is the start of the yellow arc. But it's not so much the speed, its the improved rate of climb and take off performance that would be good!

That Saturday I took two young boys flying in my Gazelle, from West Sale. I saw the Cougar parked across the ramp in the grass. We had a fantastic time. Both boys said to me when coming in to land "This is the best day of my life!", too funny! They had a ball. I did the obligatory positive and negative G turn and gentle wingover, at 1500Ft, as much as you can do in a Gazelle. The one lad at the start, was a bit cautious, so asked if I could just fly around. I said absolutely, I will do exactly what you want me to do....But he soon was enjoying it and went for the gentle "G" demo...I got the "toy houses and cars" comment too! A week or two before I was up solo at 2000Ft, doing power on stalls and unbalanced stall....even a Gazelle will drop a wing! Can't get my head around that, literally a half hour after I departed, having put the Gazelle away, three young men went out in that Cougar and died!?? Makes me sick. The pilot had around 600Hrs? But what upset experience? This looked like a steep angle impact. It looks like a stall spin scenario? With 600 Hrs experience I like to think an engine failure should have resulted in a landing in a paddock, even a hard landing. But also could have been stalled in a forced landing. Terrible, terrible event...what price for experience?? My Air Force training, and experience are invaluable as they keep me safe. I've seen too many horror incidents. I am not a daring pilot, If there's a play.....I play it safe.... Aviation can be extremely brutal.....but I guess so are the teen hooning car crash tragedies? But again....is upset training and accelerated or "G" stalls; severely neglected these days? I think so. I walked out once I locked the hangar, and had a look at the Cougar. Must have as I said, just missed these guys....would I have maybe said something, chatted about the conditions (it was getting hot and was getting turbulent below 1500 Ft as was forecast. Would that have changed things? Probably not. Can't say I liked the Cougar proportions much..... it has a lot of keel area ahead of the wing, the engine being very far forward. The tailfin is small, just eyeballing it, I thought directional stability can't be great? Short span but broad chord wing. The winglets are large and may help with directional stability?

This could be interesting....like me, you can pick up a pretty tidy Skyfox Gazelle for under $30 000, way cheaper than any kit. With the "more affordable" (sounds better than "cheaper"😄) Zonsen, you could fully re-build the aircraft, and if changing rego to experimental, could put in a 100Hp Zonsen. All up the cost of this should be way less than a new kit? Lets face it, ZONSEN prices could keep some older recreational aircraft in the air.

Fine! You can never please everybody. I have had nothing but good and satisfactory service, from the Haval and the CFMoto bike. I don’t like Jack Daniels burbon. You probably do. I far prefer a single malt whiskey.

Yes full tanks generally better for less condensation and fume build up. But the Gazelle is limited to less than 10 litres per tank, if you hangar it and are folding the wings. I think because normally she sits on her tail skid wings folded, (although I have a tail stand which keeps it more level). This tail sit causes the greater than 10 litre fuel level to go past the filler caps which may leak or push fuel out the cap tank vent pipes located on the filler cap. In a level attitude, this does not occur. Also, I try only run Mogas, so have to use 10 litre fuel containers to refuel, so not easy to always fill tanks after every flight.