TOM BRETT'S DESIGNS-UPDATE
07-12-2009, 02:33 PM
#26
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RE: TOM BRETT'S DESIGNS-UPDATE
(tied for 1st with Brooks for our UK friends),
Ray
07-12-2009, 08:31 PM
#27
RE: TOM BRETT'S DESIGNS-UPDATE
ORIGINAL: kingaltair
The second picture shows Helen Brett and Willie McMath posing with Tom's TBX-1.
The second picture shows Helen Brett and Willie McMath posing with Tom's TBX-1.
07-13-2009, 06:53 AM
#28
RE: TOM BRETT'S DESIGNS-UPDATE
ORIGINAL: Free Bird
Thanks Duane, I appreciate the pics!
That TBX-1 is just awesome. I'm glad that it still lives. Like the Simla, it would be neat if a replica of it could be developed.
FB
Thanks Duane, I appreciate the pics!
That TBX-1 is just awesome. I'm glad that it still lives. Like the Simla, it would be neat if a replica of it could be developed.
FB
07-13-2009, 06:58 AM
#29
RE: TOM BRETT'S DESIGNS-UPDATE
ORIGINAL: Michaelj2k
Looks like a wing repair was made on the TBX-1 at the two outboard ribs on the left wing.
ORIGINAL: kingaltair
The second picture shows Helen Brett and Willie McMath posing with Tom's TBX-1.
The second picture shows Helen Brett and Willie McMath posing with Tom's TBX-1.
BTW......If you look at the picture of "Perigee" in the museum in post # 15, you will see a dent in the right leading edge, and a little torn silk. If I remember correctly, that was reportedly caused by a throttle servo locking open, and the plane running under a van at the field. Apparently it was not repaired before going to the museum. The incident happened soon before Tom left R/C for full-scale planes.
Duane
07-15-2009, 11:04 PM
#32
RE: TOM BRETT'S DESIGNS-UPDATE
Here is Tom's last design the TBX-1 from some different angles. Note the new AMA number given to Tom after winning the 1962 World Championships.
He designed, built and flew the TBX-1 in 1965. Within a year he would move on to full-size aircraft, leaving national/international competition behind. The T-tailed TBX was a very bold, innovative design, and Tom won a design award for it. In addition to the dramatic wing sweep, the TBX sported a pressurized fuel system, and a main wheel braking system. The fuel tank was located over the C/G...long before it became commonplace on the modern pattern ships.
Due to the wing sweep, the C/G was far rearward, and nearly all equipment in the plane, (servos, battery, receiver etc), was located at the back of the fuselage. The large vertical fin at the rear supporting the T-Tail may have helped balance the plane as well.
We will be discussing the TBX in detail with some surprises coming up.
He designed, built and flew the TBX-1 in 1965. Within a year he would move on to full-size aircraft, leaving national/international competition behind. The T-tailed TBX was a very bold, innovative design, and Tom won a design award for it. In addition to the dramatic wing sweep, the TBX sported a pressurized fuel system, and a main wheel braking system. The fuel tank was located over the C/G...long before it became commonplace on the modern pattern ships.
Due to the wing sweep, the C/G was far rearward, and nearly all equipment in the plane, (servos, battery, receiver etc), was located at the back of the fuselage. The large vertical fin at the rear supporting the T-Tail may have helped balance the plane as well.
We will be discussing the TBX in detail with some surprises coming up.
07-16-2009, 02:30 AM
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RE: TOM BRETT'S DESIGNS-UPDATE
Very interesting........ although I think I would describe it as a T-Tail layout rather than V. There seems to be a hatch on the bottom rear of the fuselage - is that where the radio gear is installed.
Ray
Ray
07-16-2009, 06:59 AM
#34
RE: TOM BRETT'S DESIGNS-UPDATE
ORIGINAL: RFJ
Very interesting........ although I think I would describe it as a T-Tail layout rather than V. There seems to be a hatch on the bottom rear of the fuselage - is that where the radio gear is installed.
Ray
Very interesting........ although I think I would describe it as a T-Tail layout rather than V. There seems to be a hatch on the bottom rear of the fuselage - is that where the radio gear is installed.
Ray
The radio gear and servos are located far back in the fuselage as stated in the earlier post, (but this gives me the chance to point it out twice). Back then it was very unusual to have everything back there by the control surfaces themselves, but back then you didn't have many highly swept designs either. Don Lowe's Phoenix 1 has the same characteristic. The Phoenix 1 plan calls for conventional gear placement, but in reality, I've heard builders of the Phoenix 1 talk about the hard time they have balancing it, (with 23 degrees sweep).
At least Tom knew everything needed to be aft, and it's planned for in the design. We'll take a look inside soon.
07-16-2009, 07:28 AM
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RE: TOM BRETT'S DESIGNS-UPDATE
That's me told off 
Surprising the gear needs to be S0 far back considering the weight of the huge fin and large tailplane. I thought perhaps you just meant at the rear of the wing opening. Interested to see the inside shots with the hatch off.
Ray
Surprising the gear needs to be S0 far back considering the weight of the huge fin and large tailplane. I thought perhaps you just meant at the rear of the wing opening. Interested to see the inside shots with the hatch off.Ray
07-16-2009, 08:27 AM
#36
RE: TOM BRETT'S DESIGNS-UPDATE
ORIGINAL: RFJ
That's me told off Surprising the gear needs to be S0 far back considering the weight of the huge fin and large tailplane. Interested to see the inside shots with the hatch off.
Ray
That's me told off
Surprising the gear needs to be S0 far back considering the weight of the huge fin and large tailplane. Interested to see the inside shots with the hatch off.Ray
Good going Ray!!The fin is built-up with bulkheads and sheeted like a vertical wing. It is "unique" IMHO
It seems to me Tom may have been deliberately trying to make this plane look like a full-scale aircraft, (though I don't know which one). Look at the four wheels, (I don't think he needed four wheels for weight purposes), and the rudder hinge arrangement. I was at an air museum recently, and I noticed the rudder hinges on the full-scale jet fighters look like that. It looks a little like a cargo plane, and at times like a short B-52 or something. Does anyone out there note a resemblence to a particular aircraft? I'd like to know if there is something out there that looks like it that Tom might have patterned it after?
Duane
07-16-2009, 11:02 AM
#38
RE: TOM BRETT'S DESIGNS-UPDATE
Can any of you aeronautical engineering types tell us the advantages/disadvantages of the T-stab?
The only observation I can think of off-hand would be that the elevator should be less effective at slow speeds since it is not in the propwash. At the same time since the elevator is so far above the center axis of the fuselage, might that actually INCREASE the sensitivity of the elevator? I'd like a knowledgable person to help here since I'm just guessing.
It also looks to me that the fuselage itself partially blocks the rudder, (possibly making it less effective), but that might not amount to much.
Is it likely he develped this T-stab arrangement primarily for asthetics, with no functional advantages, (and maybe even introducing disadvantages)? On the other hand, it might do a great Knife Edge Flight. Notice the caption calls it the "Lateral Are Special", (maybe a term Tom used).
Duane
The only observation I can think of off-hand would be that the elevator should be less effective at slow speeds since it is not in the propwash. At the same time since the elevator is so far above the center axis of the fuselage, might that actually INCREASE the sensitivity of the elevator? I'd like a knowledgable person to help here since I'm just guessing.
It also looks to me that the fuselage itself partially blocks the rudder, (possibly making it less effective), but that might not amount to much.
Is it likely he develped this T-stab arrangement primarily for asthetics, with no functional advantages, (and maybe even introducing disadvantages)? On the other hand, it might do a great Knife Edge Flight. Notice the caption calls it the "Lateral Are Special", (maybe a term Tom used).
Duane
07-16-2009, 12:56 PM
#39
RE: TOM BRETT'S DESIGNS-UPDATE
Capping the fin like that will make it more effective, but at low speeds/high alpha the elevator and stab will be blanked (google for Boeing 707 stall videos). The wing sweep will allow high alpha approaches with great stability, but lots of dutch roll.
It would be neat to see UStik put it into his simulator.
Andy
It would be neat to see UStik put it into his simulator.
Andy
07-16-2009, 02:10 PM
#40
RE: TOM BRETT'S DESIGNS-UPDATE
ORIGINAL: AndyKunz
Capping the fin like that will make it more effective, but at low speeds/high alpha the elevator and stab will be blanked (google for Boeing 707 stall videos). The wing sweep will allow high alpha approaches with great stability, but lots of dutch roll.
It would be neat to see UStik put it into his simulator.
Andy
Capping the fin like that will make it more effective, but at low speeds/high alpha the elevator and stab will be blanked (google for Boeing 707 stall videos). The wing sweep will allow high alpha approaches with great stability, but lots of dutch roll.
It would be neat to see UStik put it into his simulator.
Andy
When you say "blocked" ....blocked by what part of the plane?Thanks
07-16-2009, 07:48 PM
#42
RE: TOM BRETT'S DESIGNS-UPDATE
Hi Duane,
You really need Martin Simons book. For $25 from Carstens and a few hours of reading, you'll gain a HUGE wealth of info that will make all kinds of sense of what you see looking at these old Pattern planes and considering the Pattern schedule, then looking at a modern plane and its schedule. It's not hard reading - I was using sources like this (Andy Lemmon's book is another good one) when I was a kid, even before high school.
"Blanked" is when there is not a clean airflow (typically totally turbulent) for the surface to interact with. It's super easy to demonstrate. Tape a short (3"-6") length of ribbon to the back of your hand. Hold it out the window of a moving car. When the airflow is parallel to the top of your hand, note how the ribbon behaves. Now rotate your hand 90 degrees. The ribbon is now blanked.
"Alpha" is the angle of attack of a wing. A Harrier landing is a high-alpha maneuver. Hovering is post stall maneuvering (there's a difference).
A Dutch roll is when you see the tail rolling "independently" from the wings. Watch a freeflight RC conversion model with lots of polyhedral while the pilot is landing. It's dutch rolling all over the place. It's an interaction between the fin size and the di/polyhedral. Less in the wings, more in the tail, and it becomes more stable ... to a point. Go too far and you lose spin stability. Dutch roll is much preferred to spin instability. Swept wings act like dihedral, and at high angles of attack cause the same behavior. (Side note - this is why they went to straight TE's - the small amount of LE sweep acted like dihedral no matter which side was up, but wasn't enough to hurt the points when landing. Basic aero engineering at work.)
The short tail moment on the TBX also means it needs to be larger to provide adequate yaw stability. Tail moment is the distance between the tail and wing (actually very specific points). There's a nose moment also, which is from prop to the same point on the wing. (Can you guess what that point would be?) The nose moment and gyroscopic actions of the prop influence how the suddenness of actions will affect the flight of the plane. There's a reason why they have it real short on modern pattern designs, Yaks, Extras, etc.
Remember this: "An airplane is a set of compromises flying in formation."
Andy
You really need Martin Simons book. For $25 from Carstens and a few hours of reading, you'll gain a HUGE wealth of info that will make all kinds of sense of what you see looking at these old Pattern planes and considering the Pattern schedule, then looking at a modern plane and its schedule. It's not hard reading - I was using sources like this (Andy Lemmon's book is another good one) when I was a kid, even before high school.
"Blanked" is when there is not a clean airflow (typically totally turbulent) for the surface to interact with. It's super easy to demonstrate. Tape a short (3"-6") length of ribbon to the back of your hand. Hold it out the window of a moving car. When the airflow is parallel to the top of your hand, note how the ribbon behaves. Now rotate your hand 90 degrees. The ribbon is now blanked.
"Alpha" is the angle of attack of a wing. A Harrier landing is a high-alpha maneuver. Hovering is post stall maneuvering (there's a difference).
A Dutch roll is when you see the tail rolling "independently" from the wings. Watch a freeflight RC conversion model with lots of polyhedral while the pilot is landing. It's dutch rolling all over the place. It's an interaction between the fin size and the di/polyhedral. Less in the wings, more in the tail, and it becomes more stable ... to a point. Go too far and you lose spin stability. Dutch roll is much preferred to spin instability. Swept wings act like dihedral, and at high angles of attack cause the same behavior. (Side note - this is why they went to straight TE's - the small amount of LE sweep acted like dihedral no matter which side was up, but wasn't enough to hurt the points when landing. Basic aero engineering at work.)
The short tail moment on the TBX also means it needs to be larger to provide adequate yaw stability. Tail moment is the distance between the tail and wing (actually very specific points). There's a nose moment also, which is from prop to the same point on the wing. (Can you guess what that point would be?) The nose moment and gyroscopic actions of the prop influence how the suddenness of actions will affect the flight of the plane. There's a reason why they have it real short on modern pattern designs, Yaks, Extras, etc.
Remember this: "An airplane is a set of compromises flying in formation."
Andy
07-16-2009, 09:20 PM
#43
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RE: TOM BRETT'S DESIGNS-UPDATE
Greetings Everyone, I was really surprised to just fine the interest in Tom Brett and his models. I joinded the RCCD inthe summer of 1962. The first meeting I attended it was announced that Tom had just won the world champs. I was a member of the club till the summer of 1968 when I moved to Oklahoma.
I do have 12 color photo of the last Invitional that was held. (1967?) I, a picture of Jimmy Greer accepting his prizes, with Tom and Helen standing in the background. 2, A full picture of Harold DeBolts orgional Acrobat biplane, that was soon to be released as a kit. 3, A
picture of Jim Kirkland with His first place prize.
I also rember a 106 driver that talked two his buddies into making a low pass in their F 84's in the middle of Kirklands pattern flight. Like the old song says "I felt the earth move under my feet". He never missed a beat and finished his flight .
Kingaltair, try talking Willie into joining us, he was their to durning those Golden years.
Al
I do have 12 color photo of the last Invitional that was held. (1967?) I, a picture of Jimmy Greer accepting his prizes, with Tom and Helen standing in the background. 2, A full picture of Harold DeBolts orgional Acrobat biplane, that was soon to be released as a kit. 3, A
picture of Jim Kirkland with His first place prize.
I also rember a 106 driver that talked two his buddies into making a low pass in their F 84's in the middle of Kirklands pattern flight. Like the old song says "I felt the earth move under my feet". He never missed a beat and finished his flight .
Kingaltair, try talking Willie into joining us, he was their to durning those Golden years.
Al
07-16-2009, 10:33 PM
#44
RE: TOM BRETT'S DESIGNS-UPDATE
ORIGINAL: AndyKunz
Hi Duane,
You really need Martin Simons book. For $25 from Carstens and a few hours of reading, you'll gain a HUGE wealth of info that will make all kinds of sense of what you see looking at these old Pattern planes and considering the Pattern schedule, then looking at a modern plane and its schedule. It's not hard reading - I was using sources like this (Andy Lemmon's book is another good one) when I was a kid, even before high school.
''Blanked'' is when there is not a clean airflow (typically totally turbulent) for the surface to interact with. It's super easy to demonstrate. Tape a short (3''-6'') length of ribbon to the back of your hand. Hold it out the window of a moving car. When the airflow is parallel to the top of your hand, note how the ribbon behaves. Now rotate your hand 90 degrees. The ribbon is now blanked.
''Alpha'' is the angle of attack of a wing. A Harrier landing is a high-alpha maneuver. Hovering is post stall maneuvering (there's a difference).
A Dutch roll is when you see the tail rolling ''independently'' from the wings. Watch a freeflight RC conversion model with lots of polyhedral while the pilot is landing. It's dutch rolling all over the place. It's an interaction between the fin size and the di/polyhedral. Less in the wings, more in the tail, and it becomes more stable ... to a point. Go too far and you lose spin stability. Dutch roll is much preferred to spin instability. Swept wings act like dihedral, and at high angles of attack cause the same behavior. (Side note - this is why they went to straight TE's - the small amount of LE sweep acted like dihedral no matter which side was up, but wasn't enough to hurt the points when landing. Basic aero engineering at work.)
The short tail moment on the TBX also means it needs to be larger to provide adequate yaw stability. Tail moment is the distance between the tail and wing (actually very specific points). There's a nose moment also, which is from prop to the same point on the wing. (Can you guess what that point would be?) The nose moment and gyroscopic actions of the prop influence how the suddenness of actions will affect the flight of the plane. There's a reason why they have it real short on modern pattern designs, Yaks, Extras, etc.
Remember this: ''An airplane is a set of compromises flying in formation.''
Andy
Hi Duane,
You really need Martin Simons book. For $25 from Carstens and a few hours of reading, you'll gain a HUGE wealth of info that will make all kinds of sense of what you see looking at these old Pattern planes and considering the Pattern schedule, then looking at a modern plane and its schedule. It's not hard reading - I was using sources like this (Andy Lemmon's book is another good one) when I was a kid, even before high school.
''Blanked'' is when there is not a clean airflow (typically totally turbulent) for the surface to interact with. It's super easy to demonstrate. Tape a short (3''-6'') length of ribbon to the back of your hand. Hold it out the window of a moving car. When the airflow is parallel to the top of your hand, note how the ribbon behaves. Now rotate your hand 90 degrees. The ribbon is now blanked.
''Alpha'' is the angle of attack of a wing. A Harrier landing is a high-alpha maneuver. Hovering is post stall maneuvering (there's a difference).
A Dutch roll is when you see the tail rolling ''independently'' from the wings. Watch a freeflight RC conversion model with lots of polyhedral while the pilot is landing. It's dutch rolling all over the place. It's an interaction between the fin size and the di/polyhedral. Less in the wings, more in the tail, and it becomes more stable ... to a point. Go too far and you lose spin stability. Dutch roll is much preferred to spin instability. Swept wings act like dihedral, and at high angles of attack cause the same behavior. (Side note - this is why they went to straight TE's - the small amount of LE sweep acted like dihedral no matter which side was up, but wasn't enough to hurt the points when landing. Basic aero engineering at work.)
The short tail moment on the TBX also means it needs to be larger to provide adequate yaw stability. Tail moment is the distance between the tail and wing (actually very specific points). There's a nose moment also, which is from prop to the same point on the wing. (Can you guess what that point would be?) The nose moment and gyroscopic actions of the prop influence how the suddenness of actions will affect the flight of the plane. There's a reason why they have it real short on modern pattern designs, Yaks, Extras, etc.
Remember this: ''An airplane is a set of compromises flying in formation.''
Andy
Duane
07-16-2009, 10:45 PM
#45
RE: TOM BRETT'S DESIGNS-UPDATE
Al;
It would be great if you could scan your photos and send them to me, or place them in the thread.
I also have photos of deBolt's Acrobat, (see below). It's funny, I've had these pictures, (kodachrome slides) for years, but there is no identification about what year the pictures were taken. My best guess is between 1964-1966, but it's just a guess. I'd love it if an RCCD "local" could tell me which year it was. I think Don Lowe won with his Phoenix, but I'm not sure.
Willie is a neat guy, and a man who truly loves to fly model planes...any kind of planes. While I limit myself to SPA-legal planes, he flys anything with wings, (and maybe helicopters too...I don't know, but I wouldn't be surprised). He is one of the most enthusiastic guys I've met when it comes to R/C...at ANY age.
I have had several e-mail and phone conversations with Willie since the present RCCD leadership put him in touch with me. I've given him links to both this forum and the Ed Kazmirski's Taurus forum, (I wished him luck with that one) He told me he's reading it a little at a time, but since he's so busy at the field, his time for reading these forums is limited.
Yes I've encouraged him to join us, and give us some insights to the times and the Invitationals...we'll see; I don't think he is an RCU member....at least not yet.
Duane
It would be great if you could scan your photos and send them to me, or place them in the thread.
I also have photos of deBolt's Acrobat, (see below). It's funny, I've had these pictures, (kodachrome slides) for years, but there is no identification about what year the pictures were taken. My best guess is between 1964-1966, but it's just a guess. I'd love it if an RCCD "local" could tell me which year it was. I think Don Lowe won with his Phoenix, but I'm not sure.
Willie is a neat guy, and a man who truly loves to fly model planes...any kind of planes. While I limit myself to SPA-legal planes, he flys anything with wings, (and maybe helicopters too...I don't know, but I wouldn't be surprised). He is one of the most enthusiastic guys I've met when it comes to R/C...at ANY age.
I have had several e-mail and phone conversations with Willie since the present RCCD leadership put him in touch with me. I've given him links to both this forum and the Ed Kazmirski's Taurus forum, (I wished him luck with that one)
He told me he's reading it a little at a time, but since he's so busy at the field, his time for reading these forums is limited.Yes I've encouraged him to join us, and give us some insights to the times and the Invitationals...we'll see; I don't think he is an RCU member....at least not yet.
Duane
07-17-2009, 07:37 AM
#47
RE: TOM BRETT'S DESIGNS-UPDATE
At normal flying speeds I would expect it to be rock solid. The sweep will ensure that. It will also come out of a hammerhead with very little wobble (the wobble would still occur, but it should be impeceptibly slow).
Low-speed flying would be different than your average plane. The planform will allow it to settle smoothly with the nose high, and maintain directly stability because the fit is capped by the stab (the fin/rudder will have air flowing into it from below, and the stab/elevator will trap it there). Pitch control will remain very positive until you get the nose too high, but that would not have been a "realistic" landing, so I imagine the pilot would keep away from that type of angle anyway.
The spin characteristics would be interesting. Once you get that inboard wing stalled, the outboard will have very little lift also because most of the air will be heading almost directing spanwise - no lift there either! The large fin would tend to stabilize it, but being so close to the wing probably wouldn't stop it. The elevator and rudder should still be very effective (again, air is being pushed into a corner), so recovery would like be by down elevator and centered rudder. I bet you it would exit very cleanly, but you would probably need to get used to flying it since it would be different than normal. Also, the inside wing will have air flowing perpendicular to the LE (or close to it) creating lift. It would have a very good, natural, tendency to recover itself.
The only thing that concerns me is the long nose. It might cause some funny twitches in yaw when doing a square loop, for instance. The sweep would probably fool the observer into not seeing it. That's probably good for points, too.
The reason he built the fin as strong as he did is because it's going to be taking a beating. Lots of loading on it for every maneuver because of the stab on top.
Andy
Low-speed flying would be different than your average plane. The planform will allow it to settle smoothly with the nose high, and maintain directly stability because the fit is capped by the stab (the fin/rudder will have air flowing into it from below, and the stab/elevator will trap it there). Pitch control will remain very positive until you get the nose too high, but that would not have been a "realistic" landing, so I imagine the pilot would keep away from that type of angle anyway.
The spin characteristics would be interesting. Once you get that inboard wing stalled, the outboard will have very little lift also because most of the air will be heading almost directing spanwise - no lift there either! The large fin would tend to stabilize it, but being so close to the wing probably wouldn't stop it. The elevator and rudder should still be very effective (again, air is being pushed into a corner), so recovery would like be by down elevator and centered rudder. I bet you it would exit very cleanly, but you would probably need to get used to flying it since it would be different than normal. Also, the inside wing will have air flowing perpendicular to the LE (or close to it) creating lift. It would have a very good, natural, tendency to recover itself.
The only thing that concerns me is the long nose. It might cause some funny twitches in yaw when doing a square loop, for instance. The sweep would probably fool the observer into not seeing it. That's probably good for points, too.
The reason he built the fin as strong as he did is because it's going to be taking a beating. Lots of loading on it for every maneuver because of the stab on top.
Andy