The last Pathfinder

[John Miller]

When Gordan Delaney returned from the Nationals this summer, he had made the decision that large planes, even very good flying ones, are very dificult to finess in the winds typical of the Nat's.

This seems to agree with posts here and elsewhere from other top pilots re: size of models for wind flying.

Since then, we've been hard at work, designing his Pathfinder, the last in the series. It's a full fuselage design for a piped engine, specifically his PA .40UL.

The wing area is 650 sq. inches.  Projected weight is in the mid 50's. Of course, Trike gear.

I've included a couple of Cad images of the design for you to see. Hope you enjoy.

best wishes

John Miller

[Alan Hahn]

One comment,
Most of those I know who fly the profile Pathfinder really like its characteristics, with its simple constant chord wing. However most of the other Pathfinder's have completely different wings than the profile. Are they actually better flyers?

[Gordan Delaney]

Alan,
Yes,They fly much better. The Profile was to help people come up from beginner, interminiate,and advance fliers to learn the basic pattern and learn to fly it with more precision. Most build up bodies pipe or non pipe fly better. There much more rigid than a profile body.

Gordy

[Alan Hahn]

Gordon,
Thanks for the reply, Actually I buy into the full fuse. But my question was the wing. I figure you are unbiased in this regard.
But anyway. I have NEVER heard anyone complain about the profile. Makes me want to finish mine (I am embarrassed to admit it has been sitting 80% finished for the last 5 years. Oh the shame!

[RandySmith]

When Gordan Delaney returned from the Nationals this summer, he had made the decision that large planes, even very good flying ones, are very dificult to finess in the winds typical of the Nat's.

This seems to agree with posts here and elsewhere from other top pilots re: size of models for wind flying.

Since then, we've been hard at work, designing his Pathfinder, the last in the series. It's a full fuselage design for a piped engine, specifically his PA .40UL.

The wing area is 650 sq. inches.  Projected weight is in the mid 50's. Of course, Trike gear.

I've included a couple of Cad images of the design for you to see. Hope you enjoy.

best wishes

John Miller

Hi John 

Great  job the  plan looks  super, I am sure  Gordy is  pleased 

please post pictures

Randy

[steve pagano]

     Will this be available along with the twin pathfiner as a kit? and if so by who? I always wondered if there was a built up version of the pathfinder.

[John Miller]

     Will this be available along with the twin pathfiner as a kit? and if so by who? I always wondered if there was a built up version of the pathfinder.

Hi Steve, both of the designs mentioned will probably become kits. By whom may not be known for a while. Most likely Walter will have something to do with it. A lot depends on what the final version works out to be. We want to have the prototypes built, trimmed and flown in competition, and any changes needed, before any kits are made.

Actually, there have been 2 earlier full bodied versions built. The first one was for a .40, 670 sq inches. I flew the plane at the Tri city Nat's in 1995. The second one, was built shortly after the first one, and was powered with an ST .51. Slightly larger at 700 sq's. There was a problem with the type of full depth main spar we were using, that made the wing not quite as strong as we wanted it to be. The larger one was lost when it blew the outboard wing during a string of very tight, high G loops. a year later, the smaller one started showing a flex in the wing during manueverrs, and was retired. Still hangs on my wall.

I've made available several sets of plans for these early ones, but knowing there was a weakness in the spar, always made me a little worried, so I stopped and told those who wanted the plans to wait until we re-did the plans.

This latest version looks to have all the issues resolved and should be a very capable design. It carries the look of the originals, with a sleeker and neater profile. When the pipe tunnel was added, it laid so much mass in the fuse, that it began to resemble a B-52. It just didn't have the right look.  we lowered the turtle deck slightly, and extended the canopy. This visually changed the scale of the design and got rid of the heavy look in the front end.

Gordan and I are both waiting for the lazer cut parts now, Really anxious to get started.

As a side note, the Twin Pathfinder is hot. Both of them have the most awsome sq corners. We need a little more thrust from the pair of .15's. We think we've got that licked now, after Gordy spoke to PW at the Nat's. We were using 8 X4's, but Paul used 9 X 5's on his B-17.

As soon as the weather allows, we'll be trying out some 9 inch props. So far, on the test bench, there's a lot more thrust with the longer props.

[Warren Leadbeatter]

Very impressing looking plan.  I'm in the middle of building a Mark II profile version at the moment.  I will be putting a ST G21 .46 on mine.   

Cant wait to finish it and fly it.

Cheers

[Mike Foley]

  John,

Any idea when you might have the short kit available for the twin pathfinder? I was very impressed with it at Pasco

[John Miller]

Hi Mike, it was great meeting you at Pasco. I really enjoyed myself. I'm happy you like the twin. I really like it too, and should have it trimmed out for the next contest, at the end of the month.

I'm working on getting the prtotypes laser cut for the full bodied version at this time. As soon as I'm finished with that one, and the protos are being built, I'll have the protos cut for the twin.

One full bodied Pathfinder is being built by one of our top builders using parts he cut himself. He didn't want to wait. He's already found three little areas that need some correction. That's why we prototype them isn't it?

I was planning on two prototypes of the twin, one for myself, and one for Gordy, but if you want to build a proto, I could cut three. Of course I'd want your input as to errors, or possible changes needed. let me know, it's a few weeks out.

[Mike Foley]

>>>I was planning on two prototypes of the twin, one for myself, and one for Gordy, but if you want to build a proto, I could cut three. Of course I'd want your input as to errors, or possible changes needed. let me know, it's a few weeks out.<<<

  John, sounds good.  let me know the total cost and I can have a money order in the mail.  I assume their will be some lazer cut parts?

 

[John Miller]

OK Mike, Send me an e-mail and we'll go over the particulars.

jobelcrank@yahoo.com

[John Miller]

I posted this update on SSW, and for those who may not get over there, I'm also posting here.

The prototypes are moving along very well. Most of the sub-assemblies are finished or nearly so.

Gordy is almost finished with the wing, with the controls in, and the flap linkage worked out. I'm a little behind him as I took a vacation during January, but both of the proto's should be ready for covering at about the same time. The other Proto being built in Ca, from hand cut parts, is ready for covering.

Some minor changes have been made to the CAD file as we encountered errors, or came up with a different method during construction. They should be very accurate once we're ready to release the plans.

There's some consideration being given to a "short kit" that would contain all the cut parts, as well as the gear and canopy, but still questioning the interest and feasability of that option.

Here are the pic's, starting with preperation for cutting the foam leading edge buck.

[Dave Denison]

JOHN.

Great looking ship!   Many years ago I built the profile and was very pleased with the results.  Is there a set of Cad Drawings available of this ship that can be purchased?  Look forward to your reply.

    REGARDS.    DAVE

[John Miller]

JOHN.

Great looking ship!   Many years ago I built the profile and was very pleased with the results.  Is there a set of Cad Drawings available of this ship that can be purchased?  Look forward to your reply.

    REGARDS.    DAVE

It's a pleasure to work with Gordan on his designs. 

Actually it really is but we're both so hard headed, that sometimes it gets intense.

The Pathfinder series has been a good bunch of planes. Gordan says this is the last in the series, but, I hear rumblings about a full bodied twin version for a pair of .25's might be in the wings.

I'm happy that you had good luck with yours, and I'd like to let you know that Yes, once we've finished the prototypes, made the changes, and finalized the plans, the CAD plans will be available. The basic plans are two sheets as you see at the top of this thread. There's also a pattern sheet that will be available to those who prefer to cut their own parts. We're not yet sure if there will ba a laser cut short kit available or not.

Regards

John

[Dave Denison]

JOHN.

  Thanks for the great info on the plans and short kit.  If there is a  list building, for plans or "short kit" please, put me down on same.  Hope to see more of your building progress as it comes alone.

      REGARDS.   DAVE.

[John Miller]

Thanks guys, I'm sure Gordy is very pleased with your comments on this, his latest design. He has a knack with them I believe, as they seem to look right, and fly right. Proud I am to be able to be a small part in the development.

We're keeping score, so that will help in any decisions regarding short kits. The plans will definently be available once we've made sure that everything is as Gordy wants it.

here are some pictures I downloaded last night. They are mostly of the wing build. I posted these over on SSW as well.

The series shows how we used the definatly edge shear web as part of the jigging structure, as well as the use of tabs on the ribs, rib alignment spacers, and bits of the structure itself to align and jig the wing.

I cannot add text between the pictures here as I did on the other site, so If you have questions, try checking out the other site first, then ask here if your question was not answered for you.

Gordan has more, and better pictures of the wing build, and as soon as I can get them into my computer, I'll post them.

[Gordon Tarbell]

I would prefer kit but a short kit would be fine . please put my name on the list.If more info is needed to get me on the list let me know. Gordon Tarbell

[Mike Spiess]

WOW that makes it almost too eazy

[Dave Denison]

Hi John.

    I'm looking for more of your photos of the fuse and wing!   Is there more progress?  I guess I'm in need of a "Pathfinder fix"!!
    I'll check back later.

    REGARDS.    DAVE

[John Miller]

Ah, yes there's been progress. Both Gordan and I have the sub assemblies finished, and are working on the fuselages. Mine is in the jig. it's all glued up, but I want to take some pictures before I remove it.

Gordy is working on the front top block and the cowl. It's shaping up real pretty.

More pictures are on the way, I promise.

[John Miller]

As promised, here's more pictures of the Last Pathfinder project. I took these yesterday, so they are about as up to date has I can get them.

Gordy and I both have finished the subassembly's, and started on the fuselages.

I wound up with a problem with my flaps being, at first stiff, but too heavy. I cut out the centers, warren trussed inside the openings, and got the weight down while keeping most of the stiffness. Well, the gremlins of the shop had some fun with me because a few days later while preparing to install the horn clips, It was obvious that they had warped more than I was comfortable with.

We came up with an idea that if I sheeted the flaps with 1/16" balsa, and biased the grain slightly, that we could convince the flap to stay straight. It worked, and they are really stiff, but, now weigh more than they did before I started trying to lighten them up.

I'm watching the weight , and after all the "bits" are finished, I'll check to see if I can finish within my finished weight budget. This means I'll probably have to build a new set of flaps...

The first 5 pictures show Gordan's wing, stab, and elevator assemblies. There's a picture of him holding the fuse with the shaping  that's been done one the nose.

The rest of the pictures show my fuselage, in the jig, out of the jig, and as it is prepared for shaping of the nose.

We used small, but very strong magnets to secure the elevator horn access door. This really works slick.

I'm considering using them on the cowl as well, but since the nose gear is mounted to the cowl, I'll include a back up  that can be used if the loads are more than the magnets can handle.

Thanks for your interest in this project. I'll be posting more pictures after the weekend. 

[Dave Denison]

Hi John.

  Thanks for the great photos!!  I'm now really enjoying my "pathfinder fix".  The fuse is looking sweet! Can't want to see some assy. photos.  I do hope the plans will be available VERY soon.......yes??
 
    REGARDS.    DAVE

[John Miller]

Here're some more pictures of the prototypes being built from this weekend.

Most of the work was expended on the cowls. The nose gear is mounted to the cowl, as the plane was designed for a rear exhaust engine. we've done this type of gear mount before, starting back in '94 with the original full bodied Pathfinder I flew in the 95 Nats. Experience has shown us that this mounting method is as strong, or stronger than other methods, and as light as well.

We did find a few minor problems with the design as drawn, versus what we were doing, but the problems only exist when using different power plants than the one shown. I plan on making some notes and modifications on the plans to reflect what we've learned.

So, starting out you'll see the balsa/Plywood laminated nose ring, Then we'll see one of the methods used to mount the nose gear to the cowl. Shaping the cowl is next, and the next to last picture is the fuse with the bottom tacked on and shaped.

The fuselage is almost ready to have the wing joined to it.

The last picture is of the balsa plug we made to form the canopy on. It's not finished yet, but getting close. 

Thank you for your interest, it's been an enjoyable build so far.   

[john e. holliday]

Thought my eyes were deceiving me, but, where do you find the needle nose like spinner?  The build looks great.  Has Gordy got his flying yet?  DOC Holliday

[John Miller]

Thought my eyes were deceiving me, but, where do you find the needle nose like spinner?  The build looks great.  Has Gordy got his flying yet?  DOC Holliday

I'm not sure those spinners are being made any longer. I'll get the manufacturer's info next time I'm at Gordan's. The spinner was one of a pair, NIP, that he had set away for one of his twins, I suspect. I'll likely order a Russian, carbon fiber spinner from Kaz. The one on my Blue and Yellow All American Eagle is the needle nose CF I got from Kaz. I'm not sure if I'll be using the needle nose, or standard with this plane.

No, Gordy isn't yet flying his. As of Sunday I caught up with him. I think he held back so I could get ahead and make the mistakes instaed of him.

[Tom Dugan]

Regarding the Needle Nose Spinners.  CB Associates was bought by MECOA and are now available from MECOA on their website. 

Tom

[John Miller]

Regarding the Needle Nose Spinners.  CB Associates was bought by MECOA and are now available from MECOA on their website. 

Tom

Good eye Tom.

The spinner is indeed a CB Associates 2" dia.

[John Miller]

The latest pics from last weekends building session.

[john e. holliday]

Its documented, Gordy working on a plane.  Just kidding as I know he is one terrific builder, flyer and gentleman.  Later,  DOC Holliday

[Dave Denison]

Hi JOHN.

    I sure do appreciate those great photos!  How are the plans coming?  Do you have a time line for availability?

      Sorry for all the questions......but we needs to know!!  Keep up the great work!!!!

                 REGARDS.    DAVE

[John Miller]

Thank you Dave for the nice comments.

The plans have some of the changes already done, but, as soon as the prototypes are built and ready to cover, we will be sitting down at the computer and make sure that all the changes have been done.

This will occur after VSC as both of us will be attending this year.

I'd say that towards the end of the month, the plans should be finished to the point that they represent what we've built. I'm not sure yet if there will need to be some slight changes made to reflect what is needed to trim the planes out for competition.

I suspect that Gordan will want to hold the plans until the planes have been trimmed out, so we know that the design is ready.

[John Miller]

It's been a little over a week since returning from VSC. What a great time that was.

I came back ready to launch into this project, but got put down by a cold or flu, whatever it was, it set me down for a few days.

Gordan has made great progress with his Pathfinder. It really looks good too. He says that in his opinion, it's the best looking Pathfinder of all the versions that have been built.

He should be ready to start covering soon. Me, I'm in the stages where there's a lot of small detail stuff to do. I spent most of Saturday making a new set of flaps. The originals got real heavy after I tried to lighten them up and they warped, then I tried sheeting them to remove the warps. Oh, they were straight, and very stiff, but weighed in at 3.6 oz's. The new flaps are 2 full oz's lighter, straight, and stiff enough.

Leather fillets were used for the wing-fuse joint. Epoxy- micro balloons on the stab. It has been decided to not have any fillet fairlings for the elevator because, depending on how the plane trims out, they're often not lined up properly, and appearnce points could be lost.

The canopy was cut from a standard Sig 16" canopy, and it looks like we'll not have to pull our own this time.

Notice the louvers on the hot air exhaust. Nice touch.

Here are the pictures from this weekends session.

The first two are of Gordan's assembled for weighing. The design weight is 55 oz's. It looks good to make that weight.

The third pic is of Gordan's back on the stand for fitting the gear doors. Note the louvers.

The rest are of mine, first sitting on it's belly prior to making and installing the main gear wires. The rest show it on the gear, with the rear blocked up, since the engine was not installed. The last shows a closeup of the nose so you can see the cowl and canopy better.   

[john e. holliday]

Too much fun in the sun.  Glad your getting better.  Maybe this will cheer you up. DOC Holliday

[John Miller]

Looking at the picture, I can't help wondering if I'd buy a used carr from myself???

Here are a couple of pictures from the last two weekends work on the pathfinders. They are both covered with Polyspan, and have some of the clear coats on. They should soon be ready for silver, and or color.

Mine weighs in at this point, with the tank in place, and all parts accounted for except the engine package, and wheels, at 34.6 oz's. Gordans is about an ounce or two lighter, but his engine package is heavier, so they both should weigh within an ounce of each other. It seriously looks like the design weight of 55 oz's will be met.

The pictures show the cockpit details on mine, and Gordan's on the paint stand.

The last shot is a drawing showing the color and trim scheme I'm planning on for mine. just imagine black where it shows white.

[Mark Scarborough]

Looks good John! are you bringing this one to the Regionals with you this year? its only a couple months away now you know?