2023 Year End Update

 Hello Everyone,

Well, hard to believe it's the end of the calendar for another year.  I had a great summer and fall, but unfortunately, I lost my medical after AirVenture and have not been able to work since.  I'm fine and going through the steps required now to get my medical back.  If all goes as advertised and predicted, I will have a surgery in early January with a 90 day recovery period.  After that, I can apply for a new special issuance medical and hopefully get an answer back on that by late May or early Jun (currently the FAA is running 12-15 weeks out on special issuance medicals).  Then,  I should be heading to re-qualification training in late June or early July of 2024 for my return to the line.  The good news is that I should be getting a lot of time in the shop this spring to and be able to get lots of  Prowler Aviation projects done (or at least, farther down the road).  OK, enough about me, lets talk about Prowlers!

So, I have a fairly short and straight forward update this time.  This update is just going to cover these ownership and builder updates:

A.  Two completed Prowlers have changed hands;
B.  Update on the French Prowler;
C.  Update on Vaughn's Prowler Status;
D.  Update on Bryan's Prowler plans;

A.  Two completed Prowlers have changed hands:
    1.  Kit #14 - This kit is completed and certified.  In Summer 2019, Steve Rogers donated his airplane to the Port Townsend Aero Museum.  I covered that in a previous update (here) last year.  Earlier this year, the museum turned around and put the plane up for sale and it was purchased by none other than our own Bryce Mitchell.  You may recall Bryce also owns the Red, White & Blue plane (the first production kit an the 2nd completed Prowler built by the original Prowler Aviation in 1990's).   So, now both Kit #1 and Kit #14 are owned by Bryce and they are both based at the Auburn, CA airport!  Here is a pic that Bryce sent me when he got the airplane safely (trailer-ed) to it's new home in Auburn in Nov2023:

I'm really glad you were able to get your second Prowler, Bryce!  Bravo!  And, I know you're looking forward to getting that plane in the air!

    2.  Kit #16 - I was talking to Ray last month, and he mentioned that Bud, too, had sold his airplane.  I don't have a lot of details yet.  But I hope to get in touch with Bud soon and find out about where his plane went.  More to follow!

B.  Update on the French Prowler - Francis continues to be the most active Prowler builder (currently - at this time).  He has been steadily completing parts and components over this past year.  In my last update, I missed a few progress pictures that he sent me prior to the last update.  Here he is showing the MLG with the hydraulic actuator and most of the linkage mocked-up and temporarily installed:

Here is another view:

It is awesome to see the MLG going into your plane, Francis!!!   After everything was fitted and functioning - it was "off to paint:"

Since then, I have gotten several more updated from Francis.  In a previous update, I showed Francis' work on building his MLG uplocks.  Here is a pic of those installed in his center section gear wells:

Francis designed his uplocks to use aftermarket auto door latches (followed Ray's lead on that) with posts mounted into the ends of the MLG yokes.  It looks like a superb setup!  Great craftsmanship, Francis!!

Here is an outstanding idea that I have not seen used by any other Prowler builders yet.  Francis fabricated some round pins onto some plates that fit into the center section wing spars (the same place that the outboard wings are mounted).  Then, he fabricated a stand with receivers for those round pins at the top of two posts.  This allows him to set the (nearly) completed center section on a stand that can be used to rotate the airplane to whatever angle he needs to work on his current project.  Check this out:

What an awesome idea!  This will, no doubt, make it much easier to work on the landing gear, then flip the center section over and work on the cockpit floor, brakes, etc.  Very good!

Here are a few pictures of some of his work on the cockpit floor that ended with the temporary installation of his foot wells for the aft pilot station:

Looking great!

I shared with Francis how I make the U shaped brackets that hold the lower end of the follow-up doors on the MLG.  Here is his mandrel that he fabricated and used to make these brackets:

And, here is one of them installed on the door and holding it to the lower end of the upper strut:

I think that his brackets turned out better than mine!  Francis is an excellent fabricator and I have been sending a lot of information to him so that he can make his own parts for the plane.  I've been doing this for a couple of reasons.  The main reason is that it is time consuming and expensive (for him) to have me send him aircraft parts.  Shipping is expensive and then he pays a premium to import "stuff" to France.  If I send him the info he needs to make the parts himself, all he has to do is find the material there to make it from.  The secondary reason is that several times I've been busy with other projects and I don't want to slow down his progress while he has to wait for me.  And, maybe the final reason is what you see above - most times he does a better job than me!  As always, outstanding work on your airplane, Francis!

C.  Update on Vaughn's Prowler Status - Recently, Vaughn's focus has shifted to planning for (and working on) his FWF solution for his Prowler.  He is going to install a rotary engine in his plane.  He has this PowerSport rotary FWF setup installed on his RV-8:

This is a 2 rotor setup in his RV-8.  He will be installing a 3-rotor engine in his Prowler.  His mechanic is working on the engine and Vaughn has begun to plan for it's installation.  We have been discussing W&B issues to try to determine how much more forward he will have to install this lighter engine + PSRU+ prop combo to get roughly the same CG range as the previous Prowlers.

At the same time, he has begun to mock up his FWF with the longerons and horse collar that I fabricated for him (shown in a previous update).  Check this out:

He has decided to start with the motor mounts that George used.  These will get modified, but he's going to try to begin with these as something to build off of.

Yup!  It's beginning to look like a Prowler! 

Excellent progress!  Vaughn has told me that he wants to set up things with his "engine guy" so that he can make this FWF system available to other Prowler builders who might want to also install a rotary engine system.  When the time comes, I'll also talk with the PowerSport folks so we can formalize a FWF package for the Prowler.

D.  Update on Bryan's Prowler Plans - Bryan has not been doing much on his Prowler the past several years.  There are many reasons for it, but mostly it was due to his plans to use a diesel engine in his Prowler.  He has sent me an update recently.  Here it is:

It’s been twelve years since I signed a purchase agreement for the engine intended for my airframe. With encouraging promises every subsequent OSH visit, my airframe languished in a dusty garage. Last year as talks (for the engine) were nearing certification I reviewed my contract with the vendor to learn that some provisions had changed, principally the financial investment required to complete the installation. I pulled the plug on that opportunity and to their credit they reimbursed me for my deposit and wished me blue skies.

Anticipating a realignment of my design goals I started the due diligence process of deciding just how best to proceed FWF. I liked what Viking Aircraft has engineered but their offerings were short of the thrust I desired for the Prowler. To rectify that issue, after consulting with several well founded suppliers I chose the Honda K20C4 engine.

On auction (recently) was an old lady’s 2022 Acura RDX that she rolled in Texas. As a successful bidder I now had an extremely durable 275 HP turbo inline 4 cylinder that wont break a sweat pulling the airframe around.  However, I was the one sweating as I learned that the factory ECU was not modifiable without all the cross talk that goes on in modern cars. Aftermarket?, hold that thought… This is a direct injected engine. Fortunately there is a supplier in New Zealand that has recently stepped onto that stage.

Next issue was that being a new car Honda still considers their maintenance data like wiring diagrams etc proprietary data. You can look at it but you pay handsomely to play. So that’s where I am at the moment.  I have to figure out just how the 14 sensor inputs relay data and create a basemap that runs the VTEC and VVT. Once that is done it will be a quick trip to Texas to pick up my PSRU and integrate it to the engine.

I am excited about this setup. If I am successful this FWF package will weigh in at 320 lbs, 100 lbs lighter and approximately 50 more HP on takeoff than the original Olds V8 that George Morse offered. It fits with room to spare in the narrow cowling with substantial space behind the engine since the block is a mere 24 inches in overall length without the PSRU. This engine just happens to be the the most coveted design for all those drifters, racers and tuners out there. I just need to infiltrate their ranks…

So, here is what Bryan's dusty plane looked like in the garage:

And:

Then, when he finished his new "man cave" the plane got "un-buried:"

cleaned up:

photo- op'ed:

and moved into the new building spot in the new building:

Here is a look at the donor car that was purchased at auction to supply his new engine for his Prowler:

The mechanic, extracting the engine from the donor car:

And, whoop, there it is!

This is the torque and horsepower plots for this engine:

This looks like an excellent choice for a FWF powerplant!  I'm not sure about the reduction ratio of the PSRU that Bryan is planning - but at about 1.6:1 the useful max RPM is around 4000-4500 RPM.  If the reduction ratio is higher, you might be able to go to 5000 RPM.  From this plot, (on this engine) the HP is well over 200. And, the torque curve is flat at 275 Ft-lbs from just over 2000 RPM all the way up to near the cross-over point which is just above 5000 RPM.  The power band (flat torque curve) and the peak HP of this engine is gong to be very usable and definitely in the range that it needs to be for delivering the max power to the prop.  Great choice!!

Here is the engine mounted on a test stand that will be used to edit, modify,  delete, test, streamline and generally prepare the engine for installation into the airplane:

This will be the place to figure out all the "issues" BEFORE trying to install the new FWF system in his airplane:

First, however, there is A LOT of wiring harness work that must be done:

Yikes!!  That's a lot of wiring to figure out!!  I think Bryan told me that he has "a guy" that will help him sort that all out.  That will be a major accomplishment when it is finished!

Thanks for the update, Bryan!

Well, that's all I have for this update.  I have not (personally) gotten much done with Prowler Aviation lately.  I've mostly been making it a priority to deal with steps I need to take to get my medical back.  Most of that will be finished my mid January and after that I'll be able to get out in the shop and get some things moving.

I hope that you all have a Merry Christmas and a Happy and Healthy New Year!