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Acro on Top

ChiefPilot

Well Known Member
I've had the itch to do some acro for the last several days - I usually am able to go at least once or twice a week but the weather has been pretty sour for longer than that. Thinking there must be a way around the issue, came up with a plan and threw it up for comments in another thread and talked with several people whom I trust & respect. Not hearing any downsides to it, I set about the plan.

The first step was verifying that the weather would be acceptable for what I wanted to do. That meant no ice in the clouds and relatively low (<5000ft) tops. Today satisfied those conditions - freezing level was about 8000' and tops were between 4000 and 5000 according to fresh PIREPS.

The second step was figuring out how to tell ATC what exactly I wanted to do. This was pretty easy and they fully approved - I simply filed a flight plan from KSGS to DOKTR, which is a fix near the airspace I usually use for acro. This was important; non-compliance with 91.303 wasn't something I wanted to get in trouble for. I added a 30 minute delay at DOKTR ("DOKTR/D0+30" in the routing) and added comments that I'd like VFR-on-top for some maneuvering 5 miles west of the airway. Filed it and away we went.

First change was that ATC offered a closer alternative via a block - a huge block, actually: MSP 090-180 radial, DME 20-40nm, block 4000-7000. A quick check of my in-beta-test app "AcroBox" (screenshots below) showed me that I could legally fly acro and stay in that block so I accepted the change and away I went. ATC wanted to know how much time I needed and to simply call them when ready to come back.

Loops, rolls, split-S, immelmann, 1/2 vertical roll, and more made the 30 minutes go by very quickly. This was the fix I needed. I also wanted to verify sustained turn radius and turn rate for some ... uh ... comparisons with potential jousting partners. Anyway...

I called ATC and asked for the RNAV GPS 34 back into KSGS and they gave it to me. Approach went without complications and I put the plane away even more impressed by the RV - most of the planes I've seen at an IAC meet would not be able to handle this mission.


On top, en-route to the aerobatic box:
23706198645_ae6a10855d.jpg


Verifying that the area I'd be flying in was away from airways and not over anything/anyone i.e. FAR 91.303 compliant (iOS sim screenshots):
23338292259_bf9ebbb601.jpg
23079192103_3c15d0dd0d.jpg


Between PRESS and ZIQPO on the RNAV 34 approach into KSGS. Hand-flown all the way.
23597692592_634c0678bf.jpg



BTW, if anyone is interested in my AcroBox app, it will be available on the app store for iPhone/iPad/etc. in the not-too-distant future free of charge and free of ads. It helps find, layout, and fly an IAC-compliant box by showing the box plus a buffer on aerial, VFR, and IFR charts. It can also act as a virtual "boundary judge" if you hook your phone/tablet into the aircraft audio system, telling you when you've entered/exited the lateral boundaries of the box and in what direction ("Box exit, north west"). I wrote it for myself but maybe others might find it useful.
 
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So what did you use for reference points? And in a spin, did the clouds have enough texture so you could judge rotation?
 
So what did you use for reference points? And in a spin, did the clouds have enough texture so you could judge rotation?

A well defined horizon is really all that was needed for the stuff I was doing - plenty of visual references so no worries there. My app took care of telling me (literally - voice annunciations) when I was in/out the lateral boundaries of a 1km x 1km box so box reference points were a non-issue.

It was a really great time - not sure I'll do this every day but it's a nice thing to have in the toolbox.
 
Oh No! $$$$$$$$$

For the last several months I've been wrestling with the decision about avionics for my RV-8. Throughout the build I've been planning/building "light and simple". (Read in VFR with IPADs). In preparation for transitioning to the RV, I spent a few days training at Patty Wagstaff's in St Augustine last month. It was a BLAST! A week or so after I got home I read a post, making note of the fact that most RV's could file IFR in order to get to the IAC events if needed, while most others remained earth bound. I've already included fuel injection, a flop tube and ratchet straps. Now, it looks like in order to be "fully" aerobatic, I'm gonna have to make it IFR.... ($). Oh well, it's gonna be a sweet ride! I'll be watching for your app!

And, oh by the way, while I was there I ran into a couple of guys that were stuck overnight "because of the weather".......



 
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BTW, if anyone is interested in my AcroBox app, it will be available on the app store for iPhone/iPad/etc. in the not-too-distant future free of charge and free of ads. It helps find, layout, and fly an IAC-compliant box by showing the box plus a buffer on aerial, VFR, and IFR charts. It can also act as a virtual "boundary judge" if you hook your phone/tablet into the aircraft audio system, telling you when you've entered/exited the lateral boundaries of the box and in what direction ("Box exit, north west"). I wrote it for myself but maybe others might find it useful.

App looks way cool. I have just been using foreflight and put an acro box sized flight plan into it. Then uploaded it to Dynon via wifi. No audio of course but at least you get the visual.... . Your app looks much nicer then that. Can't wait to try.
 
Although you pointed out 91.303, all should know aerobatics are prohibited within an 8 mile wide swatch of airspace along V airways...even if you are below MEA. In some areas an 8 mile overlap of V airway centerlines carves out A LOT of airspace!

Way back in '85, a simple roll 3 miles off the centerline of a Victor airway and 3,000' below MEA caused me a lot angst :(
 
Although you pointed out 91.303, all should know aerobatics are prohibited within an 8 mile wide swatch of airspace along V airways...even if you are below MEA. In some areas an 8 mile overlap of V airway centerlines carves out A LOT of airspace!

Way back in '85, a simple roll 3 miles off the centerline of a Victor airway and 3,000' below MEA caused me a lot angst :(

That's one of the things my app shows - the shaded area around the box represents 4nm from the edge of the box (plus a little extra margin). If the shaded area doesn't overlap an airway etc. then you're good to go.
 
App looks way cool. I have just been using foreflight and put an acro box sized flight plan into it. Then uploaded it to Dynon via wifi. No audio of course but at least you get the visual.... . Your app looks much nicer then that. Can't wait to try.

The app can share directly to ForeFlight as well as email :)
 
Although you pointed out 91.303, all should know aerobatics are prohibited within an 8 mile wide swatch of airspace along V airways...even if you are below MEA. In some areas an 8 mile overlap of V airway centerlines carves out A LOT of airspace!

Way back in '85, a simple roll 3 miles off the centerline of a Victor airway and 3,000' below MEA caused me a lot angst :(

How did they know you did the roll? You kept the same altitude---yes? Some airliner report you?
 
How did they know you did the roll? You kept the same altitude---yes? Some airliner report you?
Dumb luck. Observer on the ground clearing brush around his cabin happened to be an inspector at the Riverside FSDO. He visually followed my flight path back to KPOC and called the tower in advance of my arrival. It was my first "we have a phone number for you to call when you shut down"

It was a LongEZ, so readily identifiable back in '85 :(
 
Maybe I missed it. What is the name of you app? Is it available yet? Very cool.

It's called "AcroBox" and it's in review on the app store currently. It's been in beta test using Apple's TestFlight mechanism since mid October. I'll post an announcement here when it's ready to go.
 
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