Backcountry Pilot • Citabria 7GCBC Backcountry Performance

Citabria 7GCBC Backcountry Performance

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Citabria 7GCBC Backcountry Performance

Hey Everyone! My first post, but have read a lot of the content on this site and have thoroughly enjoyed it.

I co-own a 1973 Citabria 7GCBC. We have done quite a bit to make it into a Backcountry machine as our flying goals are to explore Alaska and open up new adventure opportunities with it. My question for those with experience with Citabria’s, specifically the 7GCBC model, is what type of STOL performance do you get out of it? And what flying techniques and/or modifications have you done that have improved the performance?

Currently we have a 150 hp O-320, an 80-40 Borer prop, 31 ABW’s, aileron spades, VG’s, Millman aluminum spars, a Scout tailspring with a wide tailwheel, baggage door, lightweight battery, and a new instrument panel with an Empty Weight of 1219 lbs (Gross legal is 1650 lbs). Quick aside: Although of course STOL performance hasn’t changed with the new instrument panel we really like having the iPad mini front and center for navigation/weather/traffic with our ADSB and the engine analyzer for monitoring of that most critical piece of equipment.

At Gross I can get in and out in about 350’ at sea level on a 60F day in no wind conditions. My final approach speed is 50 MPH with full flaps and after flare my wheels touch at 45 MPH. This gives me a bit of a margin of error on stall speed to account for general variabilities in conditions on final.

What are other pilots seeing for Citabria STOL performance? Taking sage advice I agree that the best way to improve the performance is to increase my skills and familiarity with the plane, so that is the focus, but I am curious if others have ideas on how to improve the performance, either via techniques or modifications.

Thanks for any info!
1AAE4DFB-7E6A-4FD5-B3A4-C4ADBFC56BF7.jpeg
TommyBear offline
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Re: Citabria 7GCBC Backcountry Performance

Welcome. I taught many Ag students in stock 150hp 0-320 Citabrias in the late 90s. From the back seat, I liked it better than the Super Cub with the same engine. Get the tail up quickly and the mains off quickly and stay in low ground effect and you will do fine on takeoff. Slow the airplane enough to touchdown slowly and softly wherever you want at velocity of stall with full flaps in low ground effect and you will be fine on landing. The airplane will land slow enough that, after fifty feet of ground roll, a ground loop will not destroy it.
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Re: Citabria 7GCBC Backcountry Performance

You can have a read of this article: http://www.pilotweb.aero/techniques-training/bush-flying-in-alaska-1-1572918

Sounds like you have it pretty much covered. Last time I went into the engine I did the LyCon 160 conversion which improved both performance and economy.

Didn’t say if you’d changed tailwheel, but I run a six-ply from Desser and it seems fine for what I do. Like contactflying says, the tailwheel goes on last and comes off first.

Unless I’m giving dual instruction, I remove the rear stick. ACA sells an inexpensive plastic cover for the stub, but instead my wife is missing a small metal salad bowl. No rear stick means no safety strap for the seat back, so you can flip the seat cushion forward and fold the seat back flat. Easy loading.
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Re: Citabria 7GCBC Backcountry Performance

I did a bunch of BC flying with my 76 model. I had the stock 76" prop but had it pitched back to 51, 31s, BBW, VGs and 150hp. I could touch down with power and TW first at 29kts. I really wished I would've had scout main gear on it to give me more angle of attack. I feel like that one of the best takeoff mods you could do to a 7GCBC, but I'd be a bit leery of bending something in really rough stuff. 160HP cylinders also make a nice difference, and still allows you to run 91 octane moGas.
I think the 7GCBC/8GCBC are some of the most underrated planes out there. No they aren't a supercub, but if you realize that they are an excellent bang for the buck. And they are much more comfortable IMO, wider, easier to get in, faster, awesome heaters.
Looking forward to see more pictures of your adventures!Image
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Re: Citabria 7GCBC Backcountry Performance

Thanks for the info guys! Much appreciated.

It was interesting reading that article. It is similar to my approach to short takeoffs and landings but there are a few tweaks I’m going to make based on that information and see what difference that makes. Thanks for sharing!

The Scout gear legs are something we’ve been considering. We actually have line of sight on a pair that are drilled for the 7GCBC. The only real downside I’d see would be the stiffness. Like you said, would I bend something else in the airframe if we’re in the rough? Tough to tell if it would be worth it in the long run. Going to investigate that further... Anyone else have experience with Scout gear legs on a 7GCBC?

The hp increase sparks my interest, but being able to cruise around the backcountry for an entire day and only spend $85 on 87 octane is really, really nice. Our engine only has 500 hours on it so perhaps when it’s ready for an OH we’ll do the conversion. Do you guy see a big difference between 100LL and 87 octane? Suppose I should get out there and compare the TO distance numbers.

A couple of other question I’d have is what empty weight you guys were able to get your Citabrias to? Ours is 1219 lbs currently. If you got it lighter, how’d you get there? Also, we have a Gross Weight of 1,650, but I’d heard anecdotally that that GW was based on the need to perform at gross at large +\- G’s for aerobatic maneuvers, and that if you kept it within the non-aerobatic G’s +\- you’re fine at up to 2,000 lbs. Anyone have any further insight into this?

Thanks again for the feedback!
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Re: Citabria 7GCBC Backcountry Performance

You wrote: "Also, we have a Gross Weight of 1,650, but I’d heard anecdotally that that GW was based on the need to perform at gross at large +\- G’s for aerobatic maneuvers, and that if you kept it within the non-aerobatic G’s +\- you’re fine at up to 2,000 lbs. Anyone have any further insight into this?"

Since there is no published data for flying the aircraft over the max certified GW, and since doing so would violate FARs, I doubt you're going to get anyone to answer such a question in a public forum, visible to the FAA.

Many airplanes are certified for a maximum GW when operated in the "Normal" category, and a lower maximum GW when operated in the "Utility" category. For example, the Rockwell Commander 114 I previously owned was certified at 3,140 lbs (Normal category), and up to 2800 lbs (Utility category). Likewise, the Grumman AA5 series aircraft are allowed a higher max gross weight (2200 lbs) in Normal operations, and a lower GW (1850 lbs) in Utility operations. Those max allowable GW ratings are pretty much proportional to the difference in the max load rating for Standard category (3.8G) versus Utility category (4.4G).

However, in the case of the 7GCBC, the aircraft designer / manufacturer (Champion, then Bellanca and even later - American Champion Aircraft) were issued a type certificate that allows the same gross weight for Normal category operations as it does for Aerobatic category operations. Likewise, the Bellanca POH for the Citabria line shows no allowable difference in the gross weight between the two types of operations, although it does call for more restrictive aft CG limitations when operated in Aerobatic category. Maybe they knew something we don't know?

To my knowledge, the only way to legally increase the max GW of the Citabria line (7 series) is to replace the wooden wing with a factory metal wing, which adds 100 lbs to the max GW, and appears to increase the empty weight by about 70 lbs or so, depending on your paint scheme.
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Re: Citabria 7GCBC Backcountry Performance

Thanks for the reply JP! Much appreciated. Did not mean to insinuate violating any FARs, I was just curious about design, construction, and testing as I am looking to learn as much as I can about the history behind this plane as the POH is very basic and finding material online from 1973 is well... challenging.
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Re: Citabria 7GCBC Backcountry Performance

Even the metal spar 7GCBCs are only 1750lb GW. Unless you go up to 180HP then I think you can get 1950lbs. So I wouldnt say you can go to 2000lbs. Although I'm sure it's been done successfully before...
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Re: Citabria 7GCBC Backcountry Performance

Interesting exercise, trying to figure out how a manufacturer arrives at a gross weight. Landing gear limitations maybe? Put the GCBC on floats and you're good to 1800 instead of 1650. Looking at type certificate A-759, rev 73, miscellaneous (619) you can fly it at 2325 lbs in restricted category with some airspeed restrictions, no concern for gear there. Factory metal wings, but not Milman wings, take you to 1750 - is that just an incentive from ACA in an effort to limit wood spar liability or a legitimate engineering improvement? New production 7GCBC gross is 1800, is part of that from aluminum gear legs?

My plane is 1150 empty, I could save another 13 lbs with the aluminum gear, but then I'd probably go for the slightly longer Scout gear and only save 5 lbs.

Too many variables in backcountry flying to fixate on gross weight. What does your weight have to be to get off that gravel bar in xx feet and clear those xx high trees at the end, in a tailwind because the trees are a lot higher going the other way :D . Like JP256 says, you will never enter more than 1650 in your log book, but I wouldn't rely on that to be safe, legal yes, but not safe.

Where can you still find 87 octane?
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Re: Citabria 7GCBC Backcountry Performance

Just some food for thought,

The wood winged 7GCBC weight go up to 1800lbs on edo 2000 floats. The 7GCBA (ag spray plane) is certified to 2400lbs (I admit I know nothing about it's structure). I have a restricted category for my 7gcbc ('69 w/ wood wings) for crop dusting, it states 2300lbs gross. This is before CAM8 increase. Ag planes don't, under normal operation, land at gross.

According the TC, the 2004 and newer look to be the ones that allow 1950lbs with the 180hp (normal category, acro is still 1800). This is when they introduced aluminum gear.

This leads me to believe the gross weight is limited by landing gear structure.

From what I can tell on the TC, new wings allow the old 7GCBC to 1800lbs, the new wings don't modify the gear..... So maybe the gear is stronger than one thought?!
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Re: Citabria 7GCBC Backcountry Performance

Good to hear from you, Sonny. Are you spraying, teaching Ag, or both? It is sad only two Fledgling Pawnees were built by Piper. I trained in both. Citabria is fine for teaching and limited spraying, but the Pawnees crash so safely and visibility is wonderful.
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Re: Citabria 7GCBC Backcountry Performance

contactflying wrote:Good to hear from you, Sonny. Are you spraying, teaching Ag, or both? It is sad only two Fledgling Pawnees were built by Piper. I trained in both. Citabria is fine for teaching and limited spraying, but the Pawnees crash so safely and visibility is wonderful.


Dont mean to hijack. Got into flying SEAT's. Fireboss to be exact. I'm more at home on the water! I haven't exercised the restricted use on my 7GCBC. It's just for fun. it's on floats now.
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Re: Citabria 7GCBC Backcountry Performance

The gross weight change for factory metal spars is definitely related to landing gear. I was considering
the metal spars for my old 7GC, but the factory told me I couldn't get the gross weight increase because of the old oleo landing gear.
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Re: Citabria 7GCBC Backcountry Performance

Just a comment about weight issues in general: often enough the issue is not just how much weight but where it's placed. Too often when people decide to overload their aircraft, or even fully load it, it's with more "stuff", which ends up in the baggage area, leading to an excessively aft CG. Aft CG leads to very light stick forces and squirrely behavior, and it can make recovery from a stall impossible. Even staying within the weight and balance envelope with the CG at the far aft end of the envelope often creates a "different" airplane. That's especially true with 6 place airplanes, but it can be true with smaller 2 place airplanes as well.

So it's not just a strength of landing gear or other structure that must be considered when gross weight is being considered, but how that will change the handling as the CG moves aft.

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Re: Citabria 7GCBC Backcountry Performance

So it's not just a strength of landing gear or other structure that must be considered when gross weight is being considered, but how that will change the handling as the CG moves aft.


This observation is absolutely "on point" please load wisely !!!!
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