Genesis LC (Last Chapter) in paint shop...

[Bob Hunt]

How would you like to be my Fine Line tape salesman these days? I have two ships in the paint shop. In a previous thread I gave a sneak peek at my new twin, the Turning Point, and here's a peek at my latest (and probably last - although there may be a twin Genesis in the future...) Genesis. All that remains are the letters and numbers, and they will go on today, and then clear.

I've always wanted to build a Genesis with twin rudders. Joe Perovich (a very close friend of the family) recently passed away. Joe saw a drawing I did of a Genesis with twin rudders and he wanted to build one. He built a wing for the Genesis Extreme variant and was ready to start construction on the fuselage and tail when life took a tragic turn for him. So, this one is in memory of Joe Perovich, and is a tribute to his amazing spirit. He was a very talented and motivated young man who left us way too soon...

Later - Bob

[jfv]

Nicely done as usual.

[Bob Hunt]

Thanks, Jim:

And thanks also for the great stencils you did for me!

I'm waiting on a three-blade, reverse pitch 1 3/4-inch needle nose spinner that is in the mail from Frank Imbriaco. It will be painted the metallic brown as well. The nose ring opening is 2-inches, allowing a gap for motor cooling. I've always like the annular intake look, and the electric motors give us good reason to use that feature for more than just "looks."

This one has an inline motor and wing placement, but the tail is just slightly above the centerline. That makes for less of an angle on the pushrod from the flap horn to the elevator horn. This one will mount a BadAss 3515-710 Kv motor, a 5S 2800 Lipo, or a 6S 2800 Li Ion battery (2 ounces lighter than a 6S Lipo...). A Fiorotti timer system is going in, along with a Jeti Spin 66 ESC. I'm planning on using a lightened Cox/Resinger reverse pitch 11-5 three blade prop.

Later - Bob

[kenneth cook]

              Bob, it's sad to hear of Joe's passing. I know a couple of times he came to visit us flying and he brought his gigantic dog. He was indeed a character. Ken

[Bob Hunt]

              Bob, it's sad to hear of Joe's passing. I know a couple of times he came to visit us flying and he brought his gigantic dog. He was indeed a character. Ken

Yeah, he was a character, but he had a good heart and he loved stunt flying. Just a few years ago Robby, Joe and I went flying. Joe didn't have a plane with him and he looked a bit forlorn just watching. I offered him a ride on the Genesis Extreme, and he flew it beautifully. He was very careful with it, but it was evident that his skills had improved from the last time I saw him fly. So... I just let him fly out the rest of the batteries that day, and he looked better and better with each flight. There is no doubt that he had the talent to be a top flier with his own model and a bunch of practice. Very sadly that wasn't to be.

Later - Bob

[Matt Colan]

Looks great Bob! I notice some wing fences on the leading edge of the wing of that plane

[Frank Imbriaco]

Looks great, Bob !
I now remember Joe. Sad news. Much too young to pass.
If I'm not mistaken, he visited Solberg Airport with you and Robbie just a few years ago.

[Bob Hunt]

Looks great Bob! I notice some wing fences on the leading edge of the wing of that plane

Good eyes young man! They are actually holders for experimental wing fences/turbulators/flow straighteners/ DF Gates, etc. I like to try stuff... 

Bob

[Bob Hunt]

Looks great, Bob !
I now remember Joe. Sad news. Much too young to pass.
If I'm not mistaken, he visited Solberg Airport with you and Robbie just a few years ago.

Yeah, Joey did come down to Solberg one evening with Robby and me. Just a great kid.

Bob

[Dick Pacini]

Good looking plane, Bob.  Haven't run out of that paint yet?  How are you doing with your back problems?

[Paul Taylor]

Looking good Bob.

This one looked kewl to. 👍🏼

[Bob Hunt]

Good looking plane, Bob.  Haven't run out of that paint yet?  How are you doing with your back problems?

Hi Dick:

Well, actually that brown tone is a new Ford truck color. Out in the sun it has lots of red metallic highlights. The back? Well there are bad days and fair days; not so many good days anymore...   

Later - Bob

[Bob Hunt]

Looking good Bob.

This one looked kewl to. 👍🏼

Thanks, Paul:

That was back when glow fuel was $5.00 a gallon... 

Later - Bob

[Bob Hunt]

Well, between bouts of back pain I managed to at least get the Genesis done. The twin is on the back burner for a while...

This one mounts a BadAss 3515-710 KV motor, a Jeti Spin 66 ESC and a Fiorotti timer system. It's right at 60 ounces ready to fly; that's a couple of ounces less than the Crossfire I've been flying, and that thing flies really well. In fact, the Crossfire is nothing more than the 1980 Genesis with a rudder attached! It has the same wing, tail and dimensions. This one is essentially the same as those ships but with an in-line motor and wing, and a 1 1/2-inch longer nose. Oh yeah, it also has twin rudders. I just hope I don't catch them on a door or some other protrusion. So far, so good on that front...

I'm going back to .012 solids like I used to fly. In fact, I'm going back to a lot of stuff that worked for me over the years, including a reverse pitch 3-blade prop.

Unless I decide to do a twin Genesis, this is the last in the Genesis aesthetic for me. That look has sure been good to me!

The attached photo was taken just before the leadouts were served and the "electronics" went in.

Later - Bob

[Charles Carter]

Wow Bob! looks beautiful. 

Charles Carter

[Ken Culbertson]

This one mounts a BadAss 3515-710 KV motor, a Jeti Spin 66 ESC and a Fiorotti timer system.

I cant wait to see what the Genesis LC II looks like.   Love your power train.  Glad to see the Fiorotti is still your choice.   Why the longer nose?  I ask because I have added 1" to my last two.  First one flies better but that could be a host of things, second one is still in dry dock.

Ken

[Frank Imbriaco]

That ship is frightening in person !!

[Motorman]

You should recreate that Flying Models cover photo with your latest Genesis if you still have those trophies and a pair of white pants. 

Motorman

[Ken Culbertson]

You should recreate that Flying Models cover photo with your latest Genesis if you still have those trophies and a pair of white pants. 

Motorman

What about the hair?

Ken

[Bob Hunt]

You should recreate that Flying Models cover photo with your latest Genesis if you still have those trophies and a pair of white pants. 

Motorman

LOL! I still have the small trophy that is in the photo, but Orestes has the big one right now. The only white pants I have now are "tidy whities..."

If you look closely at that FM cover shot you will see that I'm not wearing the white shoes I was famous (infamous...) for. The studio where that was taken in Middlesex, NJ had a white paper background scroll and the guy who owned it refused to let me get on it with my shoes on. Several people over the years caught that and mentioned it to me.

And Ken, there is nothing I can do about the hair now. Actually there was nothing I could do about it back then either... Never my best feature.

Later - Bob

[Bob Hunt]

Just for reference, here is a photo of the 1980 Genesis. It has the same spec wing and tail as the new one and the Crossfire has. I've always liked the way that combination flew, especially in the wind. I know a lot of noted fliers don't like the swept forward hinge line, but I prefer it. The early Genesis  models had straight TE hinge lines, and so did the Saturn. They flew just fine in the wind, but they did have much more stick pressure build up at the bottoms in heavy wind conditions. The swept forward hinge line virtually eliminates that stick pressure build up in the wind.

And Ken: the longer nose is to allow the model to balance properly without having to add nose weight. The electric motors weigh less than a glow engine. I might even go longer in the future (if there is one...) after seeing Paul Walker's ship and Matt Neumann's Enterprise.

Later - Bob

[Air Ministry .]

Far Out . Nice picture . Winter here , wanna swap ! .

One of Jose's mates , they put the prop forward a few inches , went from 9 to 11 or suchlike on the Impact master tweener E
They thought it helped it no end . Ide think tangentaly it dosnt resist turns , but the thrust moment pulls the ship straight for
smooth exits , without the bobble or baulk into turns .

A case of opposites being feasable . The Typhoon with no nose ( 8 in to prop ) the lower moment to the WEIGHT of the 18 Oz Engine
has it light controlled & very smooth , & tight in squares .

Tho ' uver ' with the  L o n g moment , tracks on course in manouvres , deliberate fine ' corrections ' to defy wind distortions easily accomplished .

Think the swept hinge biases ' centering ' = Keeps the nose straight = lessens yaw from crosswinds - varying windspeed gusts .
also id think , the more it blows the more effective they are . which near the ground , counts .

Nice plane there . 

[Bob Hunt]

G'day AM:

All that may be true. I'm pasting here an excerpt from Bill Werwage's Vulcan article that I think explains why the swept forward hinge line works so well. Billy is not an aeronautical engineer, and I'm certainly not either, so the more "learned" among us might not agree with his terminology, but it is an interesting piece, and it does make sense to me.

"The most significant thing that was different about the Vulcan was the high amount of forward sweep in the trailing edge. This was done with two thoughts in mind. I wanted to keep the center of pressure (CP) from moving aft on the wing when the flaps were deployed. With the forward swept hinge line, the average flap position is ahead of the point where it would be on a straight hinge line model, and therefore when deployed the flaps would not move the CP as far aft. The effect this has is to not over stabilize the model by moving the CP too far back from the center of gravity. In other words the model would not become as nose heavy with the flaps deployed. One of the major benefits of this arrangement is that the stick pressure felt in the handle, especially in high wind conditions, is dramatically reduced. Remember, that when the flaps are moved either up or down, the airfoil is changed to an undercamber type, which increases the wing’s lift. But it also changes the point of the center of the lift, which is also known as the center of pressure.

   “On a straight trailing edge model, when the flaps are deployed, the CP moves a much greater distance, and over stabilization occurs. The results are more stick pressure, and a model that requires more input to achieve directional change. In calm conditions this is almost imperceivable, but in heavy wind it can be dramatic!

   “Another benefit of the forward sweep in the trailing edge hinge line is the effectively longer tail moment. The moment is now measured from the average of the flap’s position in relation to the stabilizer/elevator hinge line.”

Okay, whatever the reason, the swept forward hinge line suits me. The back problems I'm having might preclude me from producing many - if any - more of these things, but the swept forward TE will always be incorporated. I have reduced the amount of sweep lately, but it is still there in my new twins, and the new (last...) Genesis has the increased amount as did the 1980 Genesis and the Crossfire.

Later - Bob

[Ken Culbertson]

G'day AM:
Later - Bob

Do you use a split horn?  I assume you do.  How do you compensate for the change in the angle of the pushrod?

Ken

[Bob Hunt]

Do you use a split horn?  I assume you do.  How do you compensate for the change in the angle of the pushrod?

Ken

Hi Ken:

I do not use a split horn, and neither does Billy, even on his models that have 2 1/2 inches of forward TE sweep per panel. I did use the split horns on the 1980 Genesis and it caused me so much grief that I almost missed the 1980 World Championships.

Billy told be to put the horn drives (section of the horn wire that goes into the flap - my name for them...) right at the root of the flap. He then spilled the secret: Put the first hinge at least 5-inches out from the side of the fuselage. There is a horn bearing where the horn stakes to the trailing edge of the wing, so a hinge just outside the fuselage is not required. This allows the flap to move up and down at the root just slightly and the result is no binding at all. I know, it doesn't seem like it would work, but believe me it does.

I'm going to paste in here a section of the Genesis Saga, a book I'm writing to tell the story of the Genesis series. This section is from the part of the story just after I had lost my 1978 WC winning ship to a freak circle accident at the 1979 Team Trials where I was the Assistant Director and the person who had to fly the judges warm up flights. The accident left me with only my 1976 Nats winning ship, which was getting a little ragged from so many flights. I could have taken it to Poland, but I wanted a new ship. I had watched Billy Werwage fly his amazing Juno at the 1979 Nats to a very close second place and noted how well it flew and turned in the heavy wind encountered that year in Nebraska. I decided to design a ship with the swept hinge line like the Juno. Here's that segment of the story:

I built two versions of the new design over the winter of 1979-1980. One of them had a very long, extremely high-aspect ratio wing and tail, and the other one was a bit more normal looking. Both ships featured foam core wings, flaps stabilizers and elevators.

The one thing I wasn’t too sure about was the control linkage at the flap horn. Not having constructed a ship with a swept-forward trailing edge before, I just naturally assumed that I would need to use two flap horns and make a yoked pushrod to connect them and then use a single pushrod off one of the flap horns to the elevator horn. I had seen this setup in Bob Gialdini’s Sting Ray article in American Modeler magazine, as he used a swept-forward trailing edge on that design.

   The builds for the two new ships went fairly smoothly (remember, I built two of these at the same time), and I really stayed on them because I didn’t have a ship that I felt was good enough to fly at the World Championships. If these ships didn’t fly well, I would be cooked.

For some reason I decided to test fly the shorter span version first and get that one trimmed out. The first flight was so traumatic for me that I almost packed it in and quit. First off the engine would go lean just after the loops and not return to its initial setting. I had provided a large cooling air inlet so I could not fathom why I was getting what appeared to be thermal runaway. To add to my misery the ship had a pronounced roll at the intersection points of the figure eights. It was too touchy as well for my taste, but I already had the static CG a bit farther forward of where I normally put it.

Okay, on the ride home from that disaster I tried to figure out the problems one-by-one. Why was the engine overheating? That was a poser. There was a huge oval air inlet in the nose of that ship and the cylinder was right in line with the air blast. I called Bill Simons about this problem and he suggested that I install a Rabe-style baffle around the engine fins. This baffle was made from sheet tin stock and had a fairly small opening in the front and a somewhat larger opening at the rear. I wasn’t too hopeful that this would solve the problem… but it did! Apparently there was a dead spot behind the cowl air inlet and the stagnant air just overheated the engine. Once the baffle was fitted, the OS .40 FSR ran flawlessly. One problem solved. Thank you Bill Simons and Al Rabe!

The CG problem was easy to fix; I just added nose weight until it felt “groovy.” The reason that I had to move the CG forward was because of the swept-forward trailing edge and the position of the high point adjacent to the quarter chord. This bird just had too long a tail moment because of the sweep, and it was tail-heavy!

Okay, now I was flying patterns, but the roll problem through transition points in the figure eight maneuvers just would not go away. I tried adding and subtracting tip weight, adding and subtracting flap area via taped on area tabs, leadout positioning and just about everything else I could think of, but the roll persisted.

I had been going flying with my next door neighbor who was a very elderly man. He was in his late 80’s when I met him in 1979, and we instantly became very good friends. It turns out that Mr. Sullivan was an extremely gifted engineer who had been involved heavily in the initial development of television.

Mr. Sullivan liked all things technical and he developed a keen interest in my building and flying program. He loved to watch me fly, and I took him out to the field to show him the problem with the new Genesis. He said that it appeared to him that the model was rolling about the same amount in each direction as I did inside and outside maneuvers. He gripped the flaps from the rear and moved them in opposite directions. I could hear a noticeable “click” as he moved the flaps one way and the same click as he moved them in the opposite direction. I realized that the pushrod ends that went through the flap horns were not cinched up tight against the horns, and when pressure was applied, the ends were sliding through the horn bearings and allowing the flaps to move opposite to each other under load. “Okay,” I thought, “There are no appearance points to worry about in FAI,” so I bit the bullet and carefully cut small hatches out of each fuselage side adjacent to where the pushrods ends were soldered. Sure enough, there was considerable in and out pushrod movement evident at the horns when the flaps were moved in opposition. Mr. Sullivan grabbed the end of one of the pushrods with a pair of pliers as I heated the solder on the retaining washer, and then he pulled the slop out of the system and I let the solder harden. We did this on both sides and then checked the flaps for differential movement. There was none!

The next day we went to the field again and flew the ship. It was like a brand new model and it didn’t have any roll issues at all through the maneuvers!
I called my team mate, Bill Werwage, and related this whole story to him and he just laughed. He told me that there was no need to use the separate flap horns in the first place. He had always used a straight horn on his swept-forward trailing edge models with no ill effects. He did tell me that it was imperative to install the flap horn so that the legs of the horn were absolutely square to the center line of the wing, and that the legs that go into the flaps be installed as close to the inboard edge of each flap as possible. It’s also necessary to sand a “flat” at the trailing edge of the wing to allow the horn wire to seat against the back of the wing. This flat has to be 90 degrees to the top view center line of the fuselage.

I also later discovered that putting the first hinge out about five inches from the fuselage on either side allows the flaps to ride up and down by a few thousandths of an inch and further smooth out the control motion. I have since made several models with swept-forward hinge lines and have used a straight horn in each of them with no problems whatsoever.
I had very little practice time left before leaving for Poland after fixing all the trim issues, but the model was now showing some fantastic performance potential.

Later- Bob


   

[Crist Rigotti]

Great story!

[Ken Culbertson]

Hi Ken:

I do not use a split horn, and neither does Billy, even on his models that have 2 1/2 inches of forward TE sweep per panel. I did use the split horns on the 1980 Genesis and it caused me so much grief that I almost missed the 1980 World Championships.
Later- Bob

Loved the story.  I only asked because I have had several tapered TE wings, all on profiles and I never used a split horn.  I just assumed that with a full body you would.  The more I read about the tapered wings the more I wonder why everybody is not doing it.

Ken

[Bruce Shipp]

I remember someone of reputation said on this board or in an article/column “if you ever see me building another airplane with a swept forward flap hinge line,  break my building arm” or something to that effect. I remember because it made me chuckle 🤭.  I am hesitant to name names ‘cause I could be wrong…but I seem to remember either Ted F or Paul W.

What I take from this is that either can be made to work well, obviously.  There is an propensity in stunt ship design to incorporate a major change into an existing design and when it doesn’t fly as expected, other changes or construction variances between the two planes are overlooked as a possible cause. 

That’s what I’ve always liked about stunt.  So many ways to solve the problems.