Lowrider LSA

[Lowrider]

I used a high pressure poly-type tube that came with my kit. Nice and light and easy to position. Do you have the masters in the front? I used stainless steel braided hose from the fuselage to the wheel. This line did not come with the kit. Bulkhead fittings where the lines penetrate the fuselage. I also have no brake pedals or rudder pedals in the back. No stick or throttle either.

Spinner,

I'd agree with you on no pedal or stick but I need to do some instruction on stick and tail wheel for my kids so I need the backseat pedals and stick. They have only flown my C-170 so the stick is new to them. I may pull them out once they are comfortable and I feel OK with them flying the LSA, but then it is nice to be able to hand off the plane to a pax too or just get a break for a few minutes.

 

[Lowrider]

Folks,

From this point forward I would like for everyone to understand that I am no longer building a Bearhawk LSA, rather an LSA of my own design and for clarification, let's call it the Lowrider LSA. NO one should be encouraged to make any modifications or changes to existing Bearhawk plans based upon my comments, actions or recomendations. While I am building under the supervision of a current A&P, I have made design changes that mirror supercubs and other cub like aircraft and hopefully these will result in a good performing plane that will serve my mission in a safe and effective manner.

Thanks for your understanding and your continued support on my project.

 

[Super11XP]

0-320???!!!!

 

[Lowrider]

Clint,

Many things that I'm changing such as gear, axle, brakes and wheel upgrades, seaplane door, float fittings, extra bracing and increase in tube size and spars, use of a balanced tail and additional bracing in the tail and the consideration of using flaps and an 0-320 powerplant all are changes to the Bearhawk LSA plans so it will be substantially different from the vanilla Bearhawk LSA so it is appropriate to change the name to Lowrider LSA. I believe it will serve my needs and wants better than the original design and still come in under a practical LSA weight. I still believe the FAA should approve the "no medical" Recreational Pilot initiative and if it comes about I can upgrade the gross weight and gain back some useful load....if not, I still have an overweight LSA.

Since I changed majors 3/4 of the way thru a civil engineering degree because I was so bored I couldn't stand it...I'm not qualified to design anything so I ask that no one follow my lead in building my LSA. I am using accepted methods used a variety of certified aircraft in my construction but they are not tried and proven...YET!

To answer your question...it's becoming more than a Bearhawk LSA, thus the name change.

 

[Lowrider]

Rudder pedal connections made between the front and rear pedals. Also got tired of looking at a naked tail post so I contoured the vert. stab and welded it up to the tail post. Looks much less naked now.

 

[Dave Calkins]

I'm putting brakes only on the front pedals. .

Glad to see you moving, making decisions, and customizing your ride....LowRiderLSA

If you're instructing from the back seat, you may wish to have brake pedals there...........consider a scenario where the instructor allows the student to "get WWAAAYY out of shape" before correcting them............this scenario would make more sense if the instructor had brake pedals and the student did NOT.......or maybe adjustable stops so a student could not overcontrol brakes or rudder,,,,but the instructor would have full throw...it might be appropriate for a new tailwheel student in the first couple hours of instruction.

...just a thought.

PS.....LowRiderLSA..........I even like the name!! D

 

[Lowrider]

Glad to see you moving, making decisions, and customizing your ride....LowRiderLSA

If you're instructing from the back seat, you may wish to have brake pedals there...........consider a scenario where the instructor allows the student to "get WWAAAYY out of shape" before correcting them............this scenario would make more sense if the instructor had brake pedals and the student did NOT.......or maybe adjustable stops so a student could not overcontrol brakes or rudder,,,,but the instructor would have full throw...it might be appropriate for a new tailwheel student in the first couple hours of instruction.

...just a thought.

PS.....LowRiderLSA..........I even like the name!! D

Dave,

Thanks for the comments and for keeping up with my antics!

Ordinarily, I would agree with you on the brakes but the only ones I'll be teaching are my kids who are accustomed to my 170 using the yoke and I'm really just learnin them the stick part....I think. They do need to be slapped once in awhile with a stern "center the ball" but mostly they are capable. I tell my middle son he was conceived in a 185 at FL120 over St Augustine and I needed O2 afterwards. He doesn't believe me but then he was born in Homer.

 

[Lowrider]

Anyone have any experience with the Thermal Arc 186 TIG or the Lincoln TIG 175?

I think I have made up my mind to invest in a TIG and learn how to use it. There are lots of applications in the airplane and it seems like a useful skill to have. I have been MIGing aluminum with a spool gun but I can't build gas tanks and the like with that set up and doing stainless would also be an advantage so the TIG may be worthwhile.

Also, which works best for you, hand or pedal control? The TA 186 comes with both but the Lincoln only comes with a foot pedal and the hand wheel is a optional item, other than that they are pretty comparible.

Any comments from you TIGgers will be apprecitated.

 

[jimboflying]

I have both a Miller 250 and a Thermal Dynamics TIG setup. The newer inverter technology seems to be easier for a rookie like me. I find that I use the foot controller the most but there are times when the hand control is really nice to have. Having pulse capability helps me on thin materials.

 

[Dave Calkins]

I have a Lincoln square wave 175.

 

[Lowrider]

I bought the Thermal Arc 186 yesterday based upon a variety of recommendations to include my IA mentor. It appears to be a fine machine and I went with it mostly because of the features it has like hand and foot control, pulse and it's an inverter vs transformer based. It's about the same size as my Lincoln SP 180T which going to sell and the TA 186 will go on that cart with my argon bottle.

Number 2 son and I are getting a crash course on TIGing tomorrow from a local TIG expert...lots of CM tube practice before I go near the plane....wondered what I was going to do with all the wind chimes.

 

[Lowrider]

Well, following almost 5 hours of TIG training this afternoon I feel VERY humble. Nothing to this TIG thing if you can walk, rub your tummy, pat your head and hop on one foot alternately all at the same time. I have the utmost respect for TIG welders now and I thought I was pretty much Sierra Hotel on the gas torch, stick and MIG. We learned a lot today but the two things that stick out the most are:

1. Inverter based TIG beats the transformers hands down.
2. $450 helmets beat the pants off $150 helmets.

I'm going to bed tonight repeating to myself.....it's all about the heat...when, where and how much....until I fall asleep.

Happy Easter to everyone!!!

 

[Lowrider]

I got my wing ribs from Usher Percision thru Mark at Avipro and they look really nice. I did not get a packing list so I couldn't inventory the boxes but they did come damage free and well packaged.

I compared them to the 35B cub rib I got from Carlson and they are not all that much different in overall profile but there are differences in the web and cord so I'm anxious to get the fuselage off the table and start my spars. I found a local 10 foot brake so I'll be ordering materials for the spars soon.

Update on TIG practice...I didn't get any better while I was sleeping. I was able to run a fairly nice bead around two pieces of .035x 3/4 that I was joining together...well almost around...well... 2/3's around before burning a hole.

 

[Lowrider]

Anyone think 6 lbs 2 oz is too heavy for the front seat? That includes clecos and the bottom of the seat also has the slide rails attached but I thought I read that folks were getting Cub seats down to 2 or 3 pounds...I guess with mesh seats. CUshion will add more weight. The frame is 4130.

 

[Dave Roberts]

Seems a little heavy. Have you thought about using heavy weight Polyfiber or Ceconite on the seat bottoms. That is what a lot of builders are putting in their Bearhawks and Patrols now. I weaved aluminum strips in mine, before the fabric idea came up. Mine weighed a little less than 9 lbs with cushions and upholstery. If I were doing it again I would try the fabric idea.

Dave

 

[Lowrider]

Dave,

I have a roll of 2" wide nylon strap that I thought about using on the back since it doesn't hold a lot of weight but everytime I picked it up it seemed heavier than the .025 6061. I may try to find a small piece of polyfiber and play with that some. I could cut some lightening holes in the alum. but I think the weight may be in the 4130 and not the alum. I threw out the idea of using seat jell because it is really heavy but it feels so nice on your butt after 12 hours on the Harley. I have some time to look around but the fabric idea is worth pursuing....thanks!

 

[Lowrider]

I went heavy with the fly cutter and reduced the weight of the front and rear seats by 18 ounces total. It took about 2 hours to do the deed so it was well worthwhile to me.

Started working on the nose ribs and it became apparent quickly that I need to set up a production line to get the ribs ready to start setting them up on the spars. Lots of metal bending and riveting to be done on the wings so I guess it is time to get organized.

Several builders got into a discussion yesterday regarding whether or not the use of flush rivets on wings (planes) are really an advantage at the relatively slow speeds that cubs and cub like planes fly. There was not any real agreement so I thought I would throw out the question to you folks who build mostly fabric covered planes and see what you think....any thoughts out there....426 or 470???

 

[Dave Roberts]

That might be a question for the designer. I know flush rivets when dimpled are stronger. Did the designer figure that in when he designed the airplane and use less rivets? Personally I would go flush just because I like the nice smooth skin.

Dave

 

[Marc Davis]

I went heavy with the fly cutter and reduced the weight of the front and rear seats by 18 ounces total. It took about 2 hours to do the deed so it was well worthwhile to me.

Started working on the nose ribs and it became apparent quickly that I need to set up a production line to get the ribs ready to start setting them up on the spars. Lots of metal bending and riveting to be done on the wings so I guess it is time to get organized.

Several builders got into a discussion yesterday regarding whether or not the use of flush rivets on wings (planes) are really an advantage at the relatively slow speeds that cubs and cub like planes fly. There was not any real agreement so I thought I would throw out the question to you folks who build mostly fabric covered planes and see what you think....any thoughts out there....426 or 470???

One of my older aerodynamics texts says drag has a significant effect on acceleration during the takeoff roll. I'd have to dig the info back up to get more exact information but that would seem like the kind of thing a cub driver would care about, especially one with a limited HP budget.

 

[skywagon8a]

It probably won't make a lot of difference in your application. I would use the 426s with dimples on the leading edge back as far as the spar. Then either one for the rest of the wing. You likely will never know the difference however, you will have the satisfaction that you put your best foot forward and it will look better. Also it will be easier to clean off the bugs.

I used 426s on the bottom forward section of a flying boat once. It did make a difference. It was more slippery in the water.

 

[don d]

I used heavey duty fabric for seat bottoms and backs on my lsa. double up on regular wieght would work also. Not bad to sit on even without cushions.. Save the wieght everywhere you can.I never tried countersinking aluminum less than .032... would get pretty thin.Don

 

[Lowrider]

Thanks for the responses on rivets...pretty much mirrored the comments I heard previously. Funny that I heard the "bugs" comment from 2 different folks but I gotta agree that could be a factor. Some suggestions were to use the heavier than .016 skin on the leading edge and dimple for 426's and that makes sense to me. I think using .025 from bottom of spar to top of spar would save some effect from hanger rash and even heavy rain, not to mention those giant grass hoppers I've seen around here. Dimpling and flush riveting is no fun on thin material and that makes me want to go one size bigger too. Maybe it's easier for everyday riveters but I find it very easy to get those little oooppps marks on the skin. I know it will cost me some weight...think it's worth it for stiffer/heavier leading edge??

 

[Dave Calkins]

...I think it it "easier" to dimple thinner stuff. Don't think that you have to "SMUSH" the metal.......try a bit lighter touch and your results will be nice. You need to have a light touch and support the gun when riveting light metal also.

There is no question that dimpled skins are stronger than not dimpled and much, much stronger than countersunk.

The first advantage of flushed rivets that came to my mind when thinking of your LSA was "removal of bugs"

PS........ My findings with bonding skins.......3M 5200 marine sealant is as good as rivets!!!! WEll, in a certain way...............Many, many times when I need to take apart something that is riveted and sealed with 5200, if there is 5200 on the faces of the skins, I drill out the rivets and the skins are very difficult to pull apart!!!!!

...just saying.

 

[8GCBC]

3M 5200 is unreal. Bonded surfaces will most likely NEVER come apart again. This week I am re chaulking port holes on the sailboat with 3M 5200. Should be good for another 30+ years on the ocean 8)

USE 3M 4200 if there is any chance that the surfaces may need to separate ( with out destruction )!

 

[Lowrider]

Yes Sir!! 5200 is great!! I just fixed an ATV fender with it...stuck it together, put some 5200 in the break and smeared it on the back side....a week later and it is like new....sorta.

What's your thoughts on .025 for leading edges rather than .016 or .020?? Yes, harder to bend and heavier...is it worth it? Should withstand bug strikes better!!

 

[Dave Calkins]

....bug strikes??

..you must be taking that airplane where those HUGE moth's grow!

I'd keep the wing design on something like this (full metal wing?!) as the designer figured it.

Also, setting ones mind to saving weight (or keeping weight where the designer want's it) must stand on principle if that's what you start with.

..otherwise, you end up with 'just another fat cub'.

...funny...... fat cubs with proper wing incidence fly great. Fat Cubs with incidence, slats, and big flaps haul a load better than skinny cubs.

....so, here we are again asking what you want!!!?!!!

 

[Lowrider]

Dave,

Still not a big as the AK skeeters!!

I want a medium weight LSA that's tough and performs well at high density altitude...just looking for ideas on how to do it...horsepower, yes/no, flaps, yes/no, HD gear/brakes, yes/no. I don't want to get it in the air and regret doing something that seems like a good idea and wasn't pursued. Maybe a light plane with no flaps is the answer but I want to be able to takeoff from a 6K foot field at 80 degrees with no problems.

 

[Lowrider]

Dave,

Still not a big as the AK skeeters!!

I want a medium weight LSA that's tough and performs well at high density altitude...just looking for ideas on how to do it...horsepower, yes/no, flaps, yes/no, HD gear/brakes, yes/no. I don't want to get it in the air and regret doing something that seems like a good idea and wasn't pursued. Maybe a light plane with no flaps is the answer but I want to be able to takeoff from a 6K foot field at 80 degrees with no problems...other than that I want to put it on floats too...kinda points to HP and flaps to me. What do you folks think?

 

[marcusofcotton]

What's your thoughts on .025 for leading edges rather than .016 or .020?? Yes, harder to bend and heavier...is it worth it? Should withstand bug strikes better!!

I seem to recall reading that Bob Barrows used .016 for the wings but doesn't recommend it for others, unhappy with results and harder to work with, IIRC.

Thanks for sharing your build, very truly an inspiration for this slooow BH builder.
Mark J

 

[don d]

my LSA is so slow that I worry about bird and bug strikes from the rear