Thursday, November 15, 2007


This (pic) has really helped with the organization. These shelves are full of all the rudder, elevator, horz & vert stab, and some fuselage patterns. There are also some misc engine parts, gear parts, etc. but that will be sorted out as time goes by.

Here is a set of rolling shelves that were built to hold all of our hydraulic press patterns. These male/female dies are for pressing out bulkhead, wing rib, and some fuselage parts. The press is just on the other side of the wall to the right. Should be handy access for these heavy pieces.

WELL - FINALLY!!!! This is the humble start to our first Prowler. This is the first piece we cut from our heavy aluminum sheets. It's the center wing section main spar web. The jig saws all went south on us and they were slow anyway. I found the recip saw to be faster and easier to control and not drag shavings along to scratch the stock. It's still the HARD way to do this!

BTW - that's the "Old Master" back at it again. George just turned 80 years old recently. Wow.

This is the "somewhat" easier way to cut out all the spar pieces. We used George's metal band saw. It's somewhat easier, but it's becoming clear that there is no really "easy" way to cut this stuff quickly and practically (unless you have millions of $$ for the CNC 5' X 12' router tables).
This is laying out the fly cut for the torque tube hole in the end of the spar web. The torque tube for the gear will pass thru a bearing in this hole to support the top of the gear strut.

And... The fly cuts.

Here is the semi finished product.

What this makes is essentially an aluminum I-beam. The several laminations of strips at the top and bottom create the "flanges" and the shear web will hold it all together. When positive G's go on the wing, the top spar cap "flange" goes into compression and the bottom spar cap goes into tension. Negative G's have the oppisite effect. The whole assembly provides for the attachement of all the other wing components and gives the wing it's ultimate strength. Right now, all the pieces have rough sawed edges and must be clamped to spacer blocks and the original patterns. This assembly is then passed by a router that will clean up the edges and make the pieces all precisely the same as the original pattern. That will be the topic for the next post. Thanks for stopping by.

Saturday, September 29, 2007


Well, it may not be readily apparent, but there has been a lot going on here at Prowler Aviation the past 6-8 weeks.
FIRST - HAPPY BIRTHDAYS! September 2007 is the end of our second year as the new Prowler Aviation. We have made our last payment to George and now truly own the company. September also saw a big milestone for George. He celebrated his 80th birthday this past month with his family in Santa Cruz. Happy Birthday George!
SECOND - DAY JOBS! Both Dave and I are looking at upcoming training at work. Dave is currently in upgrade training for the A320 and I will be transitioning to the A320 sometime in December. We've both been working a lot in a effort to keep this project funded.
THIRD - SET-UP AND ORGANIZATION. The shop has been getting some final touches to get ready for building our first aircraft. I added several sections of base cabinets and a counter top for "clean" work and a double tub laundry sink for clean up.

I also have building lots of shelves and other organizational storage places. In this pic you can see the shelves for hand tools between the garage doors. There are more just out of sight in this pic. Also note the wing jig off to the right side of the pic.

I also fashioned together an aluminum storage rack that also doubles as a pattern holder for all the wing spar patterns and drill jigs. Here you can see where the 4' x 12' sheets stand vertically in the storage cart.

And here you can see the storage for the wing spar patterns and jigs.

FOURTH - ALUMINUM IS ON THE WAY! We have ordered all the aluminum we will need to build the first Prowler. We actually thought we got the first part of our shipments on Sept 25th.

Turns out this was actually a shipment of stainless steel that was destined for a company in Germantown, WI. A transposing of the last two numbers of a work order number caused it to end up at the shop by accident. It was pretty stuff, but stainless tends to make for very heavy airplanes!It has since been re-packed and delivered back to the trucking company. Our 3 deliveries will all be picked up on Oct 2nd. Wing spar building will begin soon.

Saturday, August 11, 2007

AirVenture and Prowler Nite

Well, it was another great year at AirVenture 2007. The weather didn't always cooperate, but everyone made the best of it. Got to see a lot of incredible airplanes. Some of the notable ones were: Cabi's U2, Ruff Stuff (P-38), Glacier Girl (P-38), Big Bossman (F7F), and many others.

Unfortunatley, no Prowler's were present - YET! Maybe next year!?! We did, however, sponsor an unoffical "Prowler Nite" at the Camp Scholler campground. Bryan Davies and I were able to set up his RV and our camper side by side. In the space in between, we had a cookout and invited Prowler folks, friends and family on Wed nite.

We had a great time meeting all of you and talking Prowlers for the evening.

Thanks to all of you that were able to attend. We look forward to more get-togethers in the future.

Sunday, July 15, 2007

Prowler Shop Gets Even Cooler!

During my last few days off of work I was able to spend 2 days camping in the Lassen National Forest with the family, and 3+ days doing the final assembly of an evaporative cooling unit for the shop.
Since the days are now regularly in the high 90's and low 100's, it's become somewhat of a priority to get some cool air into the shop.
It's taken a while (note the date of the first pic) since I started welding together the frame for holding up the unit to the side of the building.
But the results were worth the wait. I had a few minor setbacks during the project, but was able to find workable solutions around the issues.
Here you can see the hole for the air to enter the building. I would have liked to take out the studs, but since I didn't originally expect to mount the cooler here, the structure wouldn't support the weight of the unit if I took them out - at least not without a lot of re-building of the wall.
So the studs stayed, but with little sheet metal leading edges mounted to the front side of the studs (gotta think areodyamics!). In the end, it doesn't affect the flow much at all.

Also, to distrubute the weight of the system there is a 3"x3"x12' angle iron on the inside of the building lagged into each stud and the window headers above the windows. There are four 3/8" allthreads that carry the load from the outside into that angle iron on the inside. And the stand on the outside is lagged into the studs at serval places.
As I test ran the system the first time, the shop cooled to 78F with an outside air temp of 98-99F. So the math and science of this swamp cooler thing really does work! (see previous post).
So, here it is pretty much complete. I need to tack the small supply line and bleeder lines to the wall and paint them to match the outside. Then it will be complete on the outside.
On the inside I only have the unit wired temporarily off of an outlet. I still need to run a new circuit off of the circuit panel, but that will wait until after AirVenture.

Saturday, June 23, 2007


Sometime in early June there was some time available to put the hydraulic press that we had acquired from George back together. After getting the hydraulic ram re-built and tested it needed to be reinstalled into the press and have the top and bottom beds re-installed. It may not be visible in these pics, but there is a 1/2 inch piece of plate steel inbetween the frame and the wooden bed on the top and the bottom. The one on the bottom is even more massive because of the large stiffening flanges that are welded to the collar and the 1/2 inch plate steel. The collar merely sits on top of the hydraulic piston. The ram is actually a 50 ton bottle jack that has an auxillary port.
Via that aux port you can put pressurized hydraulic fluid directly under the piston and run the press. For now, it is just operating with the jack via the jack handle - you know, the old fashioned way! But it's good enough to allow for testing temporarily. Sometime
in the fall we will build a small hydraulic power
pack to run the press more practically. During our test runs we will look to see how much pressure is required to press the pieces that we need to make. This will determine how big (psi) system we will need. As you might image, it also determines how much $$$ it will take to build that system - the higher the PSI the more the $$$ needed to build it.


If you look back to the last "Updated Plan" I think you'll find most of the items that were layed out there have been completed. There are a few exceptions - begining the wing assembly being the most notable. However, it's always good to have goals, so here are ours:

JUN '07:
1. Finish installing Evaporative cooling unit.
2. Work the day job to make $$ and time-off in JUL for AirVenture.

JUL '07:
1. Work the day job to pay for AirVenture in AUG.
2. Family vacation(s).
3. AirVenture! The entire week!

AUG '07
1. Locate, buy, and ship (or go get) the majority of the metal needed to build our Prowler.
2. Work the day job to pay for AirVenture and metal (see #1.)
3. Begin work in earnest to build parts of our first Prowler:
Dave - Rudder, Elevator, Horz Stab, Vert Stab
Todd - Wing

SEP '07
1. Continue work outlined above.
2. Build a hydraulic power system for the press.
3. Squeeze in time for Reno.

OCT '07
1. Build a better retaining wall and water drainage system behind the shop.

Hot News - IT'S HOT!!

It's been a while since the last post. Longer than planned, but we have both been working a lot at the real (day) jobs in an effort to keep our financial houses in order.

Since the last post, it has gotten pretty warm in northern Calif. Typical summer - hot and dry during the days. The nights are much cooler - mid 60's currently. In any event, the shop is in need of daytime cooling. So there is now a window a/c unit permanently installed between the office windows. It was a modest 2 day project in all. Next up is cooling for the main shop floor. Word around here is that evaporative "swamp" cooling is the way to go. So late last year Home Depot had the last remaining units (mostly damaged) on close out. I got a really good deal on this unit and picked it up.

One of the louvered panels was damaged, but was easily replaced by calling Champion. Total cost for the new unit: less than $90 without the motor. The motor and a few other parts will provide cool air for the main shop floor for less than $200. After talking with a few folks with more "swamp cooling" knowledge than us, we finally decided on a place to install the unit. It's going to be on the exterior north wall with the entry hole cut just under the ceiling.

With some odds-n-ends angle iron laying around, we fashioned up a bracket to hold the unit to the wall. This is a pic of the outside support system.

On the inside will be an 8-10 foot angle iron (3 inch flanges) to distribute the approximate 450 lbs load along more of the wall. The inside and outside supports will be lagged into the wall studs, and then the two halves will be bolted together at several places with all-thread through the entire wall.

In the last pic (below) the 20"x20" duct will enter the shop centered on the windows and from the top of the wall down to about where the clock is.

Evaporative cooling works well in this area because of the low relative humidity.

Theororetically, an evaporative cooling unit can cool air from it's ambient (dry-bulb) temp down to it's 100% humid (wet bulb) temp. Like any system there is never perfect efficiency, but a well maintained unit can achieve 70% efficiency.
We did a recent sample calculation using current data and found:
Dry bulb temp: 99 deg Farh.
Wet bulb temp: 65 deg Farh.
Air temp entering shop = 99 - .70(99-65) = 75.8

Not too bad. Unlike A/C however, you don't try to recycle air in a "swamp cooler" system. You actually have to provide about 2 sq. ft. of open window for each 1000 CFM of air moved in order to maintain proper temp and fan motor loading. More later.

Friday, May 18, 2007


The Prower Aviation - West shop achieved a milestone today by passing the county's final inspection. We are getting much closer to working "IN" the shop, instead of "ON" the shop!

Some last minute work on painting and exterior trim boards (not for girly men)!

The Front

The North Side

I will try to have a more detailed update posted sometime in the next week.
Thanks for looking.

Wednesday, April 11, 2007


Sorry it has been a while since the last post. A lot of work has been happening, and we have opted to keep the work going in lieu of sitting down to mash the buttons to do an update. Finally, however, we've reached a short lull in the activity so it's time to get busy update the blog.
Here (in no particular order) are progress items that we have recently accomplished:


The push is on to finish the Prowler Aviation West shop. The most recent development is the role of the CDF (California Dept of Forestry) Fire Department. Turns out that because of the potential for wild fires in Nothern California, the building inspectors will not even come out to do a final inspection until you get the "Good to Go" from the CDF. Getting the nod from the CDF is not as easy as it would first appear. Turns out, you must have all the brush (mostly Manzanita) cleared out to a minimum of 100 ft from ALL of your buildings and structures (not just the building you are having inspected). Oh, oh. You must also have the trees trimmed up to 8-10 ff from the ground. OK. They are also not big fans of having tall grass growning under your decks. Ugh. So, several days in the past couple of weeks have been spent cutting & burning.




Grass and weeds are next.

Handrails have been added, downspouts installed and trim boards painted.

Still have exterior window trims to put up, some painting to do, and one exterior light to put up.
Hope to pass the final building inspection before the end of April '07.


Wing Jig - Recently took the time to research and begin assembly of our wing jig. The wing is assembled suspended on 6 posts with the leading edge pointed down. The two end posts attach at the tip ribs. The 4 posts in the middle are not yet complete because we don't have the wing spar pattern completed yet. We have to have the entire wing spar (or at least a full scale pattern of one) in order to get the exact placement of the middle 4 posts. Two of the middle posts attach at the main gear bays and the other two posts attach just outboard of the landing gear torque boxes and just inboard of the junction between the center wing section and the outboard wing sections. These two have the most critical placement. We used a large beam laying on its side for the main center part of the jig. This can also be made from simple tubing, but we happened to have this available at no cost, so we used it.

Drill Press - One tool that we will be using is a drill press. So, the time was right and the money available so a trip to the local Lowe's netted a Delta 16" Drill Press. Really haven't had much of a chance to use it yet, but no doubt it will be a most useful tool in the years to come!

Hydraulic Press - The hydraulic cylinder has been taken to a hydraulics shop and has been rebuilt and tested. The ram had been leaking and needed service. It is now back in the press. Next items up on this area:
1. Build a hydraulic power pack to run the ram. We did get a power system with the press but there are a few problems with it. We are considering whether it is more cost effective to rebuild the old or just buy/build new. Leaning toward the latter.
2. Rebuild the press tables and install them into the press.
3. Test the system for pressure, leaks, etc.
4. Run some tests to see if the system will press out wing ribs, fuselage parts, etc.

Patterns, Parts, and Jigs - We recently began starting to inventory all of the parts, patterns and jigs that we got in the sale from Mr. Morse. We decided to start on the Empanage first for a few reasons. Most importantly, these are somewhat smaller components and Dave will be able to work on them at his place while Todd starts on the wing. Here you see the parts of the tail end of the airplane. Lower right are the rudder parts, lower left are the horizontal stab, middle left is the vertical stab, and above that are the elevator parts. At the middle right are aft fuselage parts and along the top are parts still un-inventoried. Not show are the skin patterns that are too big to fit them all on the table.

Drawings and Documentation - All the drawings that we obtained as part of the purchase of Prowler Aviation have been unrolled, uncoiled, unfolded and stacked on a large table in the center of the office. It measures somewhere in the vacinity of 5-6" thick. The other documentation (binders, books, etc.) are filling a medium sized bookcase. There are also somewhere near 100 or so 3" floppy disks that go with the Apple Macintosh that we got from George. At this point, we're not sure if it will take longer to re-learn how to use a computer that requires "boot discs" or go through all the data on all those disks. It could be close. You can see that computer sitting on top of the desk in one of the early pictures posted below.

Business Cards, Hats, and T-shirts - Now that we got our new logo from the graphic desinger, we have designed and ordered our new business cards, ballcaps and T-shirts.

These were made at It's a very well organized and easy site to use to design your own business cards. You can upload any graphics that you like. For about $22 a pack of 100 shows up in about 3-4 business days.

The shirts are on order, but have not been delivered yet. We'll get a pic or two in another update.

Thanks for checking out our site and our blog.

Saturday, February 17, 2007

Updated Plan

Feb '07
1. Continue sorting through all of the documentation from George
(Manuals, plans, drawings, etc.).
2. Locate nearest supplier of sheet aluminum.
3. Install downspouts.

Mar '07
1. Build a wing jig.
2. Get hydraulic cylinder rebuilt.
3. Rebuild the press and motor/pump.
4. Layout and cut wing ribs.
5. Practice press forming the wing ribs.
6. Finish shop construction and get final inspection.

Apr '07
1. Collaborate w/ Cabi to layout and cut wing spars.
2. Begin assembling the wing.

Wednesday, February 14, 2007


Salinas, CA -Here is a picture of a Prowler from the Salinas area.
(Apparently from the Salinas Airshow in 2005):


Seattle, WA - Here is a test flight of a Prowler in late 2006.
As far as we know this is the 4th known Prowler to fly:

Sunday, February 11, 2007

Progress Report

After the most recent 6 straight days of work, Dave and I have the Prowler Aviation - West shop about 95% complete. We should have the final inspection completed by mid March.

Here is an update to the "What's Next" list from a previous Dec '06 post:

Jan '07
1. Finish painting inside of shop and office.
This was just completed 2/7/07.
2. Complete inside work (flooring, lighting, etc.)
Also completed on 2/8/07.

3. Move into office (desks, computers, bookshelves, etc.)
The office carpet was installed 1/14/07 and funiture the next day.

4. Move into shop (workbenches, tools, shelving, sink, fridge, etc.)
Some of this has been accomplished, some is still on-going.

Feb '07
1. Begin to sort through all of the documentation from George(Manuals, plans, drawings, etc.).
Dave and I took one night recently to begin reviewing this information.
There is a large amount of info and much work to be done here.
2. Research and build a wing jig.
Just getting started.
3. Locate nearest supplier of sheet aluminum.
Still on the "to-do list."
4. Collaborate w/ Cabi to layout and cut wing spars.
(He's got a plasma cutter - way cool tool!)
Cabi has made some contacts and put together a plan to get a computer-controlled plasma cutting sytem together. This holds great potential and work continues here.

Mar '07
1. Repair and install hydraulic press in preparation for punching out wing ribs.
Press has been moved into position. Cylinder must be taken to a hydraulic shop for re-conditioning. Need to work out electric motor and shop power mis-match problems.
2. Layout and cut wing ribs.
No action yet.
3. As the weather warms up, finish painting the exterior of the shop.
Took advantage of some great weather to complete the majority of the exterior painting. Only a few eves and part of one wall remain to be painted.

More recent accomplishments include:
1. Dug trench to install internet and phone to shop.
2. Moved another trailer load of "stuff" from George's hangar to Prowler Aviation - West.
3. Made progress on finishing the upper staircase landing and handrailings.
4. Lots of landscaping, spreading gravel, and engineering rain water drainage.

Cabi's Got His Motor!

Recently George Morse delivered a Prowler engine to John "Cabi" Cabigas for his airplane.
You can check out pics a short videos here: .
It looks an sounds great John! Congratulations.