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KHAO to KUKT 427nm. Non stop?

JFCRV12

Well Known Member
For the peanut gallery,

I’m planning this flight for the coming week. Would you take this trip non stop? Recognizing that at least one direction I’ll have a headwind...

If you would, what RPM would you target? I’m pretty sure 5000rpm at 7500 makes it relatively comfortable from a fuel burn perspective but it’s obviously a bit slower and the engine doesn’t seem as happy at that rpm vs 5200+.

There are plenty of good airports I would directly over fly if fuel becomes an issue. But zero 91 octane mogas except when I’m basically there (Hershey PA).

One figure I haven’t sorted yet is fuel burn during climb out. Should I estimate 6gph?

Anyway, curious on longest legs and rpm settings folks use on long x country (for ar v12)

Thanks!
 
Three things...

1.

Remember that it is about time in the air for fuel planning; not distance. If you have 4 hours of fuel on board, at the end of four hours you WILL be landing, regardless of the distance covered.

2.

There is NO EXCUSE for running out of gas in an airplane.

3.

HAVE FUN!
 
Great advice and could not agree more. I’ll probably just set throttle at 5200 and around 3hrs evaluate when if I need to land based on distance from kukt
 
We all have our own personal standards, some are more aggressive than others.

I plan a VFR minimum reserve of 1 hour. In the -12, a minimum 30 min VFR fuel reserve is just over a couple of gallons. I can't imagine myself flying with that little amount of fuel, even with the low fuel burn of the Rotax. I can't trust the fuel totalizer to be precise enough to handle those small numbers.

It's also a good practice to plan your fuel stop mid-trip so you aren't tempted to push on when you are getting close to your final destination.

You may consider starting more conservatively, and then building confidence in your fuel burn based on the amount of fuel you actually add from the pump. Different carb settings, etc. can make one -12 have slightly different consumption rates than another. I run leaner carb jets due to being based at 4300 ft MSL, which results in a different fuel burn.

Personally, I wouldn't attempt a 427 nm flight in the -12. But that's just me.

Be safe out there!
 
Yep, looking at a pit stop at somerset (2G9). That’s about 2hrs in. Which is what I’ll likely do. I am risk adverse despite the original question. One other thought:

Anyone ferry a 5 gallon gas container in baggage area and use that to top off along way? My biggest concern is the new style containers aren’t vented. Net, any concerns with pressure change at 7500ft? Just hate using 100LL if it can be avoided.
 
Lowest burn rate is at 10,000 feet and 5000 rpm. About 101 Kts TAS and about 576 kts range, I believe, at 3.4 gals /hr.


Extrapolate between 5500 rpm and 5000 rpm, for your 5200 rpm burn rate, at 10,000 ft. I get 105 kts, 3.7 gal /hr, 28.5 NMpg, 5:23 for air time, and Range of 555 NM.

Remember that the higher you go, when you cruise, the less drag on the plane, so you need less thrust, too, and less fuel burn rate.


Maybe look at winds aloft too, to see which various elevation has most favorable winds for your trip.

Previous owner put a 6.5 gallons boat fuel tank as an Aux tank in my plane, before I bought it. Look up the mod in "things you've modified or done to your RV-12" thread, around 2012. Also a second RV-12 fuel pump and aux fuel pumps switch and all the plumbing. Turn the switch on and in 20 minutes, the 6.5 gallon tank gets pumped into the main. About 4.7 hours useful instead of 3.5 hours with a 1/2 hr reserve.
 
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Using tank of 100LL every so often is not a problem. Doesn't even have to be figured into oil change interval if exception and not common occurrence.

Better to take whiz and buy fuel than to not take whiz and not buy fuel...
 
You can play around here flight planning and modify the variables to see how it pans out. Highest elevation and slower airspeeds increase range. Added speed increases fuel consumption exponentially, so slow down, if you need more range.

https://skyvector.com/
 
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It’s rare, but sometimes runways close for accidents. It has happened to me. There is a reason FARs require a 30 minute reserve for day VFR. I prefer at least an hour, and depending on the availability of alternates maybe more. Besides, it’s easier on the bladder,😜
 
Somerset stop it is :)

You can, but you don't have to top off at this stop, just make sure you have 5 gals reserve when you get to your destination, and top off with Mogas once in PA.

Some of the FBO's might have courtesy cars you can use if you have a couple of empty 6 gallon fuel cans, to go into town and get lunch and some premium Mogas. Have to do some research on how to do that.

Sort of depends how urgent you are to get to your destination, and convenience, or lack thereof.
 
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Yep, no doubt what I’ll likely do. Not gonna lie, while the PA mountains are not very tall, it’s nice having full or close to full fuel when I cross em.
 
It’s rare, but sometimes runways close for accidents. It has happened to me. There is a reason FARs require a 30 minute reserve for day VFR. I prefer at least an hour, and depending on the availability of alternates maybe more. Besides, it’s easier on the bladder,😜

In case your reserves become inadequate for a diversion.

At the gross weights these aircraft are built if you ever find yourself in a closed runway situation, with your emergency authority you have several options.

Declare a fuel emergency and Try coordinating with any emergency responder's/tower first. Then.

If on a long runway
Land past the incident area that has closed the runway or less favorable land prior to incident area if you know you have stopping distance available or are willing to take it in the grass.

Land on a taxiway.

Land on the grass
 
Personally my rear end and bladder doesn’t like more than 2.5 hours. However, what ever you burn down be sure to confirm your still within aft cg limits as you get to the lower tank levels. Trust me, landing outside your aft cg limit is downright ugly.
 
On long XC trips, I have a list of alternates on my clipboard for about every 30 minutes of the flight. I pick ones that have fuel available (hopefully cheap), services, and car rentals etc. That way I always have “planned” alternates for unforcasted winds, bathroom breaks and anything else that might pop up.
 
Personally my rear end and bladder doesn’t like more than 2.5 hours. However, what ever you burn down be sure to confirm your still within aft cg limits as you get to the lower tank levels. Trust me, landing outside your aft cg limit is downright ugly.

Remember, we're talking RV-12 here. The only RV where the C/G moves forward as fuel is burned.
 
forward

didn't realize that, but you're right: CG goes forward during flight ;-)
Did my W&B and CoA audit this week: small step for men, but giant leap in the process. We nearly are born, Piet and I...
356 KG and about 205 cm CG - just beyond the forward border...
Now time for some wrapping up and things...
 
In the east at this time of year "pop-up" storms and haze can surprise you just about anywhere/anytime. Good to have sufficient fuel and no urgent "calls of nature" to distract you.
 
Remember, we're talking RV-12 here. The only RV where the C/G moves forward as fuel is burned.

Actually not exactly true. In my -10 the cg moves aft with fuel burn for many loadings, but if initially loaded so cg is near the forward limit, then the cg moves more forward with fuel burn.
Easy to tell - just compare calculated cg to moment arm for fuel tank.
 
That light little Rotax 912 ULS is why the RV-12 has you sitting forward of the wing spar, and why the visibility off of the front leading edge of the wing is so good in a RV-12.
 
Anyway, curious on longest legs and rpm settings folks use on long x country (for ar v12)

This doesn't help you at all with your planning but since you asked: I've done about 7 hours at 5350rpm using the extra 25 gallons in a Turtle-Pac fuel bladder sitting on the passenger seat. Biggest problem was arranging things such that I could accurately aim into a TravelJohn...
 
Speaking of bladder vs fell capacity here’s a couple of funny stories.

First one is mine: I like to add flavoring to bottles of water that I drink during flight to keep hydrated. On the day in question is was an orange flavoring, so you can imagine what it looked like in the transparent water bottle. I landed and went into the FBO with about half a bottle I had not drank. I got some strange looks, and some downright hostile ones when I poured it down the sink in the Men’s room! Then it dawned on me!

Second story from a USAF F-4 pilot friend of mine. He was flying a night training mission and had the call of Nature. He fumbled for the piddle pack in the dark cockpit and did his business. When he landed he picked up the pack, and it was empty! He said, I still don’t know where it wen!
 
Yep, looking at a pit stop at somerset (2G9). That’s about 2hrs in. Which is what I’ll likely do. I am risk adverse despite the original question. One other thought:

Anyone ferry a 5 gallon gas container in baggage area and use that to top off along way? My biggest concern is the new style containers aren’t vented. Net, any concerns with pressure change at 7500ft? Just hate using 100LL if it can be avoided.

You can buy a 5 gallon plastic fuel jug, most of them will hold up to 5.5 gallons, and drill a 1/2" hole off center in one of the top handles, and then install your own vent, should you so choose.

https://www.walmart.com/ip/5-Yellow...l60YfTv2h3aTjp9UaYtPkoYI_wzNTDqIaAsHFEALw_wcB

or order through Amazon. https://www.amazon.com/JSP-Manufact...ocphy=9031163&hvtargid=pla-522082368626&psc=1
 
Certainly something I've considered, but for this trip, at least, I'll just bite the bullet and top off with 100LL. The plane will be due for oil change when I get back anyway as engine will be pretty close to exactly 100hrs with annual due in September. For now, I'll keep it (and the travel) simple.
 
Certainly something I've considered, but for this trip, at least, I'll just bite the bullet and top off with 100LL. The plane will be due for oil change when I get back anyway as engine will be pretty close to exactly 100hrs with annual due in September. For now, I'll keep it (and the travel) simple.
100 hrs, Hobbs or Tach?
 
I'm curious what a realistic range would be for an RV-12 ? I'm assuming there is the legal amount of fuel in the tanks on landing.

For me this would be an important piece of information since I would need to be able to fly from northern to southern CA. Let's say would it be possible to fly from KLVK to KRNM without stopping. By the specs it seems like it would be. I'm curious what others think.
 
I'm curious what a realistic range would be for an RV-12 ? I'm assuming there is the legal amount of fuel in the tanks on landing.

For me this would be an important piece of information since I would need to be able to fly from northern to southern CA. Let's say would it be possible to fly from KLVK to KRNM without stopping. By the specs it seems like it would be. I'm curious what others think.

Read the POH.

https://www.vansaircraft.com/wp-content/uploads/2019/01/RV-12_POH.pdf


Look at end of section 5 to find range, run time, elevation, rpm and fuel burn.

Then maybe plug in to SkyVector.com, and set up a Flight plan and see what you get. Looks doable, if you slow down your fuel consumption, and pick the best elevation to fly at, and at best airspeed. The flight back home is another matter. Probably a stop along the way home, for fuel.
 
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Randy,

Thanks for that reference. I'll take a closer look.

I was considering a RV-12 purchase to have a bird while I finish up my RV-7A.
 
Randy,

Thanks for that reference. I'll take a closer look.

I was considering a RV-12 purchase to have a bird while I finish up my RV-7A.

If you slow down a bit, you can save all the time for a landing and refuel, mid trip, instead just land at your destination. You WILL save time, if the distance is within the range on the POH guide.

You need 4 gallons left in the tank to take off at Vx, 3 gallons at Vy, on the Legacy model Van's RV-12.

If you buy the RV-12 IS model, you need a little more than 0.5 gallon to take off, all of the fuel tank is usable, pretty much, since the newer version fuel tank straddles the whole width of the luggage area on the 12 iS, and the fuel pickup location is different.
 
If “safety” is your primary concern...you can stay on the ground as the joke goes, or plan your fuel carefully. Make a “fuel ladder”, showing time to reach, time remaining, fuel to reach, and fuel remaining at various checkpoints along your route. If you fall behind your fuel ladder, you have to stop at a pre-determined alternate. If you don’t you continue as planned and land happy.

You don’t add safety by adding a landing and takeoff you don’t need, landings and takeoffs are where the accidents happen.

The amount of fuel required at the end is: legal daytime 30 minutes, but beyond that depends on the circumstances. Availability of alternates nearby and likelihood of weather interrupting your landing plans for example.

The five gallon can nearly full won’t expand when you climb, only the air expands. (Fuel expands with temperature so leave a little airspace). Those unvented cans don’t give off fumes you can smell. Empty, they hold at least two full pees.
 
Ended up stopping at Somerset. Put 10G of 100LL in and burned 10 more to destination. Net, answer is at least today, Non stop was not happening. Anyway, I had to pee like a race horse. Fun flight!
 
Ended up stopping at Somerset. Put 10G of 100LL in and burned 10 more to destination. Net, answer is at least today, Non stop was not happening. Anyway, I had to pee like a race horse. Fun flight!

N112YS, correct? Looks like you got either a nice tail wind for the second leg, or the throttle a lot closer to the wall and higher RPM's run to get there sooner. Coffee is a bad primer for the start of a day if you're flying.
 
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N112YS, correct? Looks like you got either a nice tail wind for the second leg, or the throttle a lot closer to the wall and higher RPM's run to get there sooner. Coffee is a bad primer for the start of a day if you're flying.

Little bit of tail but only for 10-20 min. The swirled to a crosswind from the north. And yep, pushed throttle a little bit but not much. 5200 to Somerset, about 5300 from Somerset to KUKT. Had to drop to 3500 from 7500 to avoid clouds for last 45 min or so. Could have gone over but wasn’t positive I’d have a hole to get back down at destination. So I rode the bumps. Not too bad though.
 
This doesn't help you at all with your planning but since you asked: I've done about 7 hours at 5350rpm using the extra 25 gallons in a Turtle-Pac fuel bladder sitting on the passenger seat. Biggest problem was arranging things such that I could accurately aim into a TravelJohn...

Hi Dale,

I was looking around for information about a tank to place on the passenger seat and came across your post here. You mentioned the 25 gallon turtle pac. I had checked my RV 12 last weekend and the dimensions looked like a 25 would just fit. Then I found your post. You obvious made it work. Do you have any photos or further information you would be able to share.
I am interested in how much space you would have above the bladder. Do you think a life raft would sit on top okay?
Did you transfer the fuel back into the tank from the bladder. I have a vented fuel cap that I never sealed after doing the vent mod so I thought I could connect the fuel line at that fitting. Turtle pac mentions a 12 volt system with a cigarette lighter adapter. Maybe carry a 12 volt battery. Also I was wonder about a backup manual pump. I am concerned about the load on the voltage regulation. I have done the mod to place it in the cockpit but I burnt number three out recently.
I have about 930 hours on mine now so it is time to start planning something different

Cheers
Julian
120316
 
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KHAO to KUKT 427nm, Non Stop

I have a simple rule that I have never violated. I always land with at least 5 gallons. So as I am flying along, I monitor the fuel, and as it gets down around 8 gallons I evaluate where I am going to land. I pick a spot, land, and get fuel.
The longest leg I have flown was 2 hours and 45 minutes. I need to use the restroom by then anyway. I like the 5 gallon rule because it is clear and there is no room for me to fudge on it.
 
5-gallon rule is good. That gives you one hour before empty. A lot can happen in one hour. If I’m close to home base, I’ll fly sometimes down to 3 gallons. It is a good test to see if the red warning light and annunciation are working. Twice now, I have flown down to ½ gallon remaining (actual measure after landing) when I needed to remove the fuel tank. This was done with careful flying right over the airport. The RV-12’s fuel tank is 100% usable fuel with the port at the lowest point forward. The slow-filling / slow-draining fence around the port keep fuel supplied until the tank is completely dry. Excellent design…
 
Dual XC lesson today... when all is said and done, I hope to have 5 gals left.

WHP>OXR>L-52>IZP>SZP>WHP.

I have to fly to OXR to meet instructor to get my ground lesson for XC planning first, with some E6B computer slide rule, file my first flight plan, then do the actual XC, then drop him back off at OXR at his Bonanza B35V, then fly back home.

My butt is going to be hurting on this one, I think, never been in my RV-12 that long.

Today's not the smoothest or glassiest day in the air, either...
 
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