RFguy

Archer, 180hp, non-tapered constant chord wing.

Today was goign to be a skill build / challenge Short field TO practice in Xwind. Cowra departure, 2pm flight. PA28, 20 gallons on board and me. OAT 24. windy up high. Short field TO practice with pure X wind at Young. Young (YYNG) is known for its swirling challenging winds. It's something I need to work on, only done a couple in the past year. Flaps 25 , get it up to full smoke and let the brakes go. TO roll, into wind at Cowra, gusting to 10 kts on the nose . Woops ! she wants to fly at 35 to 40 knots (instead of the usual 65) . lifts off unexpectidly with big roll wobble - I hold it in ground affect until it accelerates then off we go. lesson #1 refreshed. It's thermal bumpy down low, windy mountain bumpy up high. Not much fun. NOT a 'never flown before ' passenger day/ .... I nav myself the 31nm down to Young on the VNC , go into circuit, bumpy, 10 kts pure crosswind on AWIS, not much for the PA28 but holding off the drift feels like about 15 kts on final. Ditch full flap (40).. I want to land a bit airspeed faster with a bit less drag so the decay is not as quick...., so back to flaps 25 . I hold the approach nicely stabilized. uneventful landing bit fast not all that pretty but OK...but needs work...would get about 5/10 from judges on the fence ..... backtrack for the departure. maybe some trim change for this TO. .... Normal 0 flaps TO, generally trim a fair way back. I usualy set the trim so It will fly off when its ready, consistently and well behaved. IE it just flys off, hands off around the TOSS (60-70 kts weight dependent ) when its good and ready. But this time, after being caught a bit unaware, trim the nose down a bit more. Short field TO... a bit of left roll in with the X wind. bit gusty. But this time I am ready for a bit of excitment when its time to fly....... again it jumps off the ground before I am really on top of it, woh boy ! If I had not anticipated to unruley behaviour, then I could have put a windtip on the ground ......careful with that roll you have in - needs to be moderated and be ready for the leap off the ground ... and replaced with some rudder to hold centreline on departure a bit earlier Land back at Cowra, perfect greaser into 5 kts down the runway. Takeaways :The flaps 25 TO is more like a leap off the ground rather than a nice steady rotation and liftoff. That probably reflects my incorrect pitch / trim input during the TO roll . TO with pure crosswind with LOTS of lift dialed in , (with lift off speed about 40% below usual) in needs LOTS of attention. The roll (wing a bit down into the wind) needs to come out early and rudder in as soon as the aircraft is flying ....and held close to the ground in ground effect under we reach TOSS (65-70 kts) .

Justin if you ever decide to get a gender reassignment (I think that's the modern term) , you'll very easily be able to go with "Justine".

I fly 0.5 to 1.1 per week to maintain recency. I do it week after week after week.... and that is whether I have somewhere to go or not, "PILOT HAS TO FLY" is my mantra longer than 2 weeks and the rust starts like I said a couple of weeks ago, fly regularly and you will encounter challenges often enough that the competence to deal with them stays in your brain. fly less regularly and challenges overcome etc get lost in time and you dont remember how to deal with it.

get onto the facebook site and ask https://www.facebook.com/groups/piperwarrior/ and also https://www.facebook.com/groups/1235943279809596/

interesting.... Drop octane? -Not true according to the chemist at BP and I have it in writing . Octane increases slightly briefly. Volatiles burn off, playing havoc with controlling the vapour pressure / vapourization behaviour. the forming non soluble solids is the problematic one I thought.

Gen4 is good. I'm only selling my J230 because I have the big Piper, and need something like a Savannah as a 2nd aircraft . I do have a Thruster in the works.

There is Currendooly

fresh ULP98. if in plastic container, or place where it can breath oxygen, ditch it or use it within a month. always filter and water check. The octane doesnt fall with time- what happens is some components react with oxygen and form non soluble solids.... Avgas only if nothing else is available, or the heads run red hot (>165 cruise, >180 climb) .

Justin, what EGTs in cruise are you running on your Gen4 ? Rotax engines tends to run leaner , a little more economical on fuel. In the past Jabiru has tended to err on the rich side to stop valves dropping ..... and have been playing around with the jetting forever. This rich running exacerbated the avgas buildup issues.

mmm Agree 100% Justin with everything you have written. Yes no issue with Jab airframe- its awesome. yeah (IMO) the AVGAS de-coke is needed every 400 hours worst case, for a jab on AVGAS. a solid day's work for a four cylinder. It doesn't actually require any parts as such, except for rings, since you're likely to change out the rings if cleaning the ring lands. You might be able to do it without pulling the pistons off the conrods..... Actually a running hot jab engine might burn the avgas better.... so one's mileage may vary. run hard and hot, a gen4 is probably capable of running hot enough (since it doesnt have to live in fear of head recession) of being better with the avgas gunk. I dunno. As usual, engines that are babied tend to look worse. Jabiru Rings are cheap. $35/set Rotax rings $270/set. WTF ????!!!! Yes $270/set ! like I said, Rotax is good if you dont have to fix anything..... Jabiru factory is always helpful I think people need to watch quality of oil filters. there have been a few split. Dunno what the source was of them.

that place is so foggy I'd be surprised if that would catch on.

The thing is, the Jabiru top end overhaul, is still 1000 hours, isn't it ? which leads to a cost per hour of about 1.5x the rotax, assuming nothing in the rotax breaks..... The Jab engines still face a sizable problem on AVGAS. -- AVGAS running ----They don't run hot enough to evap/ gas the lead compounds, so this cakes-up the crown, rings, chamber, guides. and leads to a TEO/TBO of around 400 hours best. This is well known. There is no getting away from this, apart from using Decalin runup with seems to reduce/ eliminate this problem, but not recognized by Jabiru (but is by rotax). - solution - run ULP95/98. problem solved. Don't run ULP more than a couple of months exposed to air. Lesser evils I'm not sure they've completely got on top of the rather inelegant oil pressure control. There's many documented problems. It's OK, just...... and I would have liked to see a heavier thru bolt, since the margin between [ sufficient preload AND the material yield AND tension errors due to torque application on unknown lube threads } They've gone to much high temperature rated valves, which is good. and about 3x the price per valve, as expected. and I they've gone to a more solid, non split skirt/crown piston. Gen4s broke alot of pistons before they got that part of it stable..... Head recession should be a thing of the past. the bolted head , like everyone else, should solve that. In the past, head recession (due to less than ideal choice of aluminium) led to valves hanging open and loss of valves.... Nothing economical is perfect. -glen

Gen4 is OK now. Had a shaky start. (2017 to 2020) I'm going to sell my J230, umming and ahhing whether I do a top end overhaul and sell with a late Gen3 (and the last of them) even has the prop frange dowels..... or I put a Gen4 in it and flog it with that..... Jabiru have had to change from the Bing carb to some Mikuni copy. so far so good, wonder how their jetting is going, that might take time to figure out.

Today's ADSB example... coming into cowra from SW this morning.. I hear chatter on the radio, couple of training aircraft in circuit.... AND I can see them on my tablet. I've done my 10 mile call a bit back.... I am 3 miles out, I see on the tablet UQM turning downwind, and MUB climbing after TO roll. I can see a conflict coming if I continue... I say nothing on the radio to startle the chickens I slow down , flaps 10, and put in a couple of S turns... and add about a minute to my join timing, which fits perfect. as a join, UQM is mid base and MUB is late downwind , I pipe up on the radio with single breath "cowra traffic Cherokee DRF joining early downwind 15 will go number three to UQM and MUB , traffic cowra. super simple. reply on radio was "MUB copy". With no ADSB , I would get on the radio at that 3 mile point, IE about a minute or two prior to joining circuit and get everyone's position, figure out where everyone is , there would be a bit of rdio chatter.....and then I'd probably do those S turns or an orbit, OR overfly above circuit and swing around for a mid field cross wind join. Cowra shares CTAF with 5 nearby ADs, the radio can be quite busy.