JAS

My Feedback: (2)

It was REALLY windy the last round. I'm gonna look into those cool little wind meters that the soaring guys use. It's always fun to know what the actual conditions we fly in are.

a) Same as Chad. Because I was borrowing planes, I didn't practice in heavy winds and probably could have used a few flights in them.
b) Was relieved I wasn't right after Andrew It was noticed that one of the top 4 finishers were also 1st up in a round during the finals.
c) Glad I knew how to read aresti; that horizontal vertical rolling 8 is a pain to write out on the call-sheet. I learned from my TOC/IMAC beginnings. My 1st IMAC Nats I did a Humpty wrong cause I didn't know how to read aresti. I learned shortly after that how to.

Alejandro, 54's

And not that I care about the debate on which power system is better (everyone likes what they like, that's why we are all entitled to our OWN opinion), but one thing I've found setting up so many planes is that one persons "1/2 throttle" isn't always what another persons is.

apereira

You are right Jason,

Sometimes I mention things where actually others fly completely different set-ups or not even fly this size of planes nor F3A, this is the more difficult part on a debate I guess as I assume others understand what I am saying.

lasers200

Just burned my 16th gallon on YS no deadsticks no problems just runs.






I would argue that the main driver for people deserting IC power is reliability. There's little point having all that power if it's unreliable. It's better to finish than not finish at all IMHO...

Regards,
Jason.
[/quote]

Jason Arnold

You should buy a lotto ticket then.. :-)

I used to be a glow flyer but have since made the switch to e-power on everything and don't regret it one little bit. The overall cost of my hobby has dramatically reduced because of this change. At roughly $100 a US gallon for 15% nitro fuel you have spent $1,600.00 on fuel. For that out lay you would have done ~400 flights or about $4 a flight. I have some F3A Unlimited packs that have over 100 flights on them. They cost me $240 for a 10S pack (2 x 5S) so the cost per flight is now less than $2.40. The more flights I get, the cheaper it gets.... For those on a budget e-power is the way to go undoubtedly.

Having said all that, everyone to their own. Some people love to tinker and wear everything in their airframe out. They also love the constant maintenance that comes with glow power. I would rather spend my time doing other things... :-)

Regards,
Jason.

MTK

Diameter trumps pitch for the current flying styles of slow and slower. E's need pitch to maintain some amount of forward speed since their rpm's are lower.

The small gassie we flew 3 years ago was lacking in ability to turn really large diameters. Fast forward to today, diameters are being turned that are at least on par with the E's but at 20% higher rpm and 20% lower pitch. Low speed still requires tremendous thrust which one can only get from large diameter. Thrust, simply put, is pulling in and throwing back an air tube. The bigger the tube the bigger the thrust

My mid throttle position on my 2 stroke gassie is turning around 6K rpm not 4K. At 6K the 10.5" pitch works just fine while the 20" diameter produces terrific thrust. Same prop at 4K wallows around the sky. Somebody will have to prove to me that the 4 stroke really has the right pull turning the same prop as mine but turning it at 4K. I'm from Mysseuri on that one (no offense to all friends from the show me state)LOL!!

MTK

Congrats....How many 24 oz tankfuls is that? No YS break downs in 25 hours of flight time is pretty kool

mwick

JAS said " It was noticed that one of the top 4 finishers were also 1st up in a round during the finals. "

I know that Andrew led off in Unknown #1 and that Brett led off in Unknown #2 but don't remember who led off for the F rounds. Obviously the way Andrew was flying, it didn't make any difference, except for possibly spots 2, 3, and 4. I'm sure with the conditions in round 4 Brett would have loved to been down the flight order a few spots. but with the way Jason flew the last 3 flights it probably wouldn't have made any difference. But that's the luck of the draw and no complaints.

Jeff Boyd 2

I'd rather not know,Jas . . It would do my head in ! ;-D

A friend once saw a bird launch itself and crash in the wind . . he said "That's it, I'm packing up . . even the 'experts' can't fly in it" lol

JB

bjr_93tz

Interesting, despite the problems I had with my YS in the first 12 months, (bearing failure, CDI sensor failure and a cooked ring?), since my last rebuild in October last year, my YS has run like a train and I've pushed at least 60l (~16 USgal) of homebrew 20% nitro 10% oil through it without a single deadstick as well judging by the number of empty 20L drum of methanoly laying around the house. The main needle has only needed an occasional click or two either way since finding it's happy spot.

Since the last rebuild, everything with it has just clicked into place so I can't say a bad word about it now, but before I would have happily melted it down into a thick, rough, cylindrical form and sent it back to Yamada with some suggestions on what they could do with it.

For the record my homebrew (20%nitro,10%oil) costs ~$5.56 AUD/litre (~$20usd/USgal) and about 300cc would get me through a schedule (~$1.70aud/schedule) excluding engine wear and tear which would add another $1 per flight worst case.

To be honest though, I like the smoke trail. Electric's and IMAC's just look lost in the sky without it, but I think F3A is moving on and I doubt I'll buy another IC engine for F3A purposes.

mjfrederick

When I was judging the first round of F I actually saw this happen. Between pilots I noticed a bird come up from a patch of tall grass just off the edge of the runway. He was trying to fly into the wind. After flapping his wings as fast as he could for about 15 seconds and getting nowhere, he gave up and landed.

OhD

How windy was it? In the old days there was a maximum wind specified for FAI meets. I remember a team selection meet in Hutchison, KS I believe, that was cancelled after a few days due to the wind being out of spec. We all went home after a very long trip when all we did was race empty beer cans down the runway. Anyway, if we knew the max wind velocity we could select our propulsion systems to handle it.

Also can anyone tell me what props folks are running on the YS and what the rpm is?

Jim O

DAMBUSTER

As far as I know the Official F.A.I. max wind speed is 12 mt/sec.I also believe that at or above this wind speed at major events such as World Champs the competitors are asked if they wish to continue flying.
Cheers Dambuster.

serious power

Hi,
Did you score the landing .

Brian

riot3d

Hi Jim,

I'm running my 175 with 20.5 x 10 PN, about 7,250 rpm.

Adrian

apereira

At the WC in Argentina, the wind speed was above the limit, but the thing is everybody (around 200+ people) have their fixed travel plans, so usually, unless there is something very severe, they will not stop the competition, the flying was awful but never stopped. The implications of cancelling the competitions or delaying will cost thousands of dollars just for the re scheduling.

Regards

OhD

Well after talking to Chip and thinking about it some more, I can understand why he is thinking of using an IC engine and I believe I can make a case for why he is right. Before all the electric guys get their blood pressure up, I must say this logic will not apply to most of us so don't go out and sell your electric stuff.

The reason is not a difference in power. Adrian's YS is putting over 3000 watts into his 20.5x10 prop and electric motors can do the same. The difference is energy. The engine can put out 3000 watts for eight minutes straight if it needs to (400 watt-hrs), but the electric pilot must manage his throttle because he only has 175 Watt-hrs total in his battery (5.000 amp-hrsx35 volts). So now we have the perfect storm. A final round that is exceedingly ENERGY hungry with many vertical knife edge maneuvers and high winds requiring more energy. Chip didn't run out of batteries but only because he flew a less than optimum pattern that conserved energy. He said he would have loved to be able to punch it like Brett was able to do.

It is amazing to me that the rules permit the IC engine powered planes to be weighed without their required energy source. One of the key components determining their performance.

Anyway, unless you plan to fly many energy consuming maneuvers in high winds stay with electric. Then again if you want to fly for 16 minutes per flight to practice.....

Jim O

Doug Cronkhite

My Feedback: (34)

I'm fairly certain this is just a hold-over from the days when electrics just weren't practical, and that nobody has been able to come up with a measuring standard that is fair to both powerplant types. If I were king, I'd say 5kg ready to fly.

The reality is electrics are 1 battery evolution away from never having to worry about this again. Where IC engines get larger and heavier to develop more power, batteries are only going to get smaller and lighter as they evolve. In talking with some friends of mine in the electric truck industry (as in Class 1 trucks), that evolution is here, it's just very expensive at the moment. When this tech trickles down to our hobby level, it'll be the same technology shift as Li-Po's were to Ni-Cd batteries.

serious power

Hi Jim,
That's all very fine and true.
However how did the guy's that came 1st and 2nd do it.
They had the very same constraints.
To pick out this one aspect just does not seem to compute.
Is it being suggested that if he had IC as well as Brett that they would both have beaten Jason.
Jason has already said that he had little or no wind practice and yet he could beat the YS is those testing conditions.
There is an expression (it's probably universal); ' A poor workman blames his tools '.
Is all this a case of that ?.

Brian

OhD

Hi Brian,

You are right but this whole discussion is not about Andrew and Jason thinking about YS power. And it isn't about Chip implying that he would have done any better this time with a YS. I am just reporting what his thinking is for the future and I can see his point. It is conceivable that at a future contest the schedule and environmental conditions might require even more energy consumption and be even more favorable to the IC engine. I am not suggesting anyone else should switch to IC engines and I doubt if many will.

Jim O

JAS

My Feedback: (2)

Mike,

I should have stuck with the first version of my sentence: It was noticed that each of the top 4 finishers had started a round in the finals. [I was 1st in 1st F, Andrew was 1st in Unk 1(2), Chip was 1st in 2nd F and Brett was first in Unk 2 (1)]

mwick

Jason:

Isn't that a coincidence; but I guess I'd rather see it that way than any other.

OhD

Brian, I read my statement again and maybe my wording was not good. When I said I could make a case for why he is right, I didn't mean he was right to switch to an IC engine, I meant his thinking was right that he didn't have the benefit of unlimited use of his power due to limited energy. If he believes there is a high probability of that happening again, then he probably will switch but most of us don't have to consider that probability. Hope this helps.

Jim O

rcpattern

My Feedback: (45)

You guys apparently need to do a better job drawing starting orders. Lol. Once the first round was set, the rotations were by the defined number of pilots rotating. I personally would like to see two different draws. One for Fs and one for unknowns. Then just invert the order for the second. This would eliminate any flight order draw giving an advantage or perceived advantage. Not that I think it truly affected any outcome.

Arch

serious power

Hi Jim,
Ok.
That though is another topic really.
I must admit that when I saw post 17 I was annoyed some and I felt it was unfair to both E power and to Brenner's unit.
I'm not sure as to the correct interpretation of the new rule re K factors.
Either way,so long as the pilots choose the maneuvers, it is likely that a good few of them will be using E power.
They would be wise to keep that in mind while choosing if they think that their 'fuel' will run out.

Brian

JAS

My Feedback: (2)

Ready for 'hot topic #2'?

We didn't pick our unknowns, which was nice for once not having dinner after 10pm the night before the finals. The K's were 74 per the rulebook, 3-K6's and 4-K5's so all was good. The unknowns were kind of boring as far as differences between them because almost every turnaround had to have a snap in it to get to the total K up to 74. So basically we did Stall Turns with 1 1/4 snaps down, 45 Humptys with Snaps, 1/2 Cubans with snaps.... in both Unknowns.

Watching the EC's it seems that the total K of 74 wasn't used and the Unk's there had a nice variety of maneuvers.

Have I not found the most recent rendition of the rulebook?

And Arch, Great job that you and your 'Team' that ran the Nats did. Not sure how you pulled off that F3A flight order in the finals, but nice job