skymaster f-86diet?
04-14-2008, 08:32 PM
#1
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skymaster f-86diet?
well the ad says 16-17 # mine with scale detail and fullsize pilot and working speed boards 24 1/4#
engine is jet central falcon
stock tailpipe
supplied fuel tanks + uat
matchboxes, jettronic gear sequeencer, jettronic brakes
jr 8411''s all around , 9411 on rudder
gyro
2-6 volt nicads-recr 1400mah each
2 cell lith 4800 ecu
1# lead in nose for correct CG
POINT IS GUYS THIS JET NEEDS TO HAVE 20# + thrust to fly this bird , keep that in mind if you add all the goodies to one!
the 16 -17# weight is impossible to get to
engine is jet central falcon
stock tailpipe
supplied fuel tanks + uat
matchboxes, jettronic gear sequeencer, jettronic brakes
jr 8411''s all around , 9411 on rudder
gyro
2-6 volt nicads-recr 1400mah each
2 cell lith 4800 ecu
1# lead in nose for correct CG
POINT IS GUYS THIS JET NEEDS TO HAVE 20# + thrust to fly this bird , keep that in mind if you add all the goodies to one!
the 16 -17# weight is impossible to get to
04-14-2008, 11:21 PM
#5
RE: skymaster f-86diet?
Gerry,
The specs on the SM website should be totally revised. Mine weighs 24lbs and we found out that it will not fly (for long) on a P-60. The tailpipe supplied by SM is 3.5" dia which is not the correct size for a 14lb thrust motor. My SM F-86 is being repowered with a P-80.
V..
BTW: your Saber looks awesome...
The specs on the SM website should be totally revised. Mine weighs 24lbs and we found out that it will not fly (for long) on a P-60. The tailpipe supplied by SM is 3.5" dia which is not the correct size for a 14lb thrust motor. My SM F-86 is being repowered with a P-80.
V..
BTW: your Saber looks awesome...
04-15-2008, 06:29 AM
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RE: skymaster f-86diet?
barry -going to fly it next wed and thurs in sarasota.
john, intake will be fine when flying , and on ground hatch will be off , with open install there is plenty of air.
david carter in fla. is flying his w/a p120
john, intake will be fine when flying , and on ground hatch will be off , with open install there is plenty of air.
david carter in fla. is flying his w/a p120
04-15-2008, 09:30 AM
#7
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RE: skymaster f-86diet?
Gerry
Very nice and unusual paint scheme. Skymasters (And they are not alone!) always underestimate the weight of their jets. It is a most frustrating habit, if you have bought a jet for a particular turbine and it ends up being not enough power![:@]
John
Very nice and unusual paint scheme. Skymasters (And they are not alone!) always underestimate the weight of their jets. It is a most frustrating habit, if you have bought a jet for a particular turbine and it ends up being not enough power![:@]
John
04-15-2008, 10:03 AM
#8
RE: skymaster f-86diet?
Hi,
I know there''s such a thing as a pipe being too small for a given engine, but I didn''t know there was such a thing as one being too big. We tried some different pipes on a Starfire, including the smaller diameter pipe that we bought for a Simjet 1200 and a Tamjets P-120 pipe. There was no difference in performance AT ALL with the bigger pipe and smaller engine. In fact, the plane ran much cooler on the larger pipecontrary to what several experts predicted.
I know there''s such a thing as a pipe being too small for a given engine, but I didn''t know there was such a thing as one being too big. We tried some different pipes on a Starfire, including the smaller diameter pipe that we bought for a Simjet 1200 and a Tamjets P-120 pipe. There was no difference in performance AT ALL with the bigger pipe and smaller engine. In fact, the plane ran much cooler on the larger pipecontrary to what several experts predicted.
04-15-2008, 10:43 AM
#10
RE: skymaster f-86diet?
ORIGINAL: Vincent
Shawn,
I had the discussion with an expert on the subject...Bob Wilcox. He said the 3.5" intake pipe with 3.25" exit is sized for the P-80-120 motors and it will create a large dynamic thrust loss for the P-60.
V..
Shawn,
I had the discussion with an expert on the subject...Bob Wilcox. He said the 3.5" intake pipe with 3.25" exit is sized for the P-80-120 motors and it will create a large dynamic thrust loss for the P-60.
V..
Vicente,
That''s great. I''m just saying what actually happened in deliberate experiments we conducted when we got different answers from different experts.
04-15-2008, 10:54 AM
#11
RE: skymaster f-86diet?
ORIGINAL: YellowAircraft
Vicente,
That''''s great. I''''m just saying what actually happened in deliberate experiments we conducted when we got different answers from different experts.
ORIGINAL: Vincent
Shawn,
I had the discussion with an expert on the subject...Bob Wilcox. He said the 3.5" intake pipe with 3.25" exit is sized for the P-80-120 motors and it will create a large dynamic thrust loss for the P-60.
V..
Shawn,
I had the discussion with an expert on the subject...Bob Wilcox. He said the 3.5" intake pipe with 3.25" exit is sized for the P-80-120 motors and it will create a large dynamic thrust loss for the P-60.
V..
Vicente,
That''''s great. I''''m just saying what actually happened in deliberate experiments we conducted when we got different answers from different experts.
Undoubtedly, a small engine will run cooler with a big tailpipe. It would even be cooler at half throttle or not running at all!
. I think that the big pipe/small engine problem is compounded by the minimal intake area. There is simply no extra air to augment the thrust that the large bell mouth needs. It would be interesting to see the installed thrust of a Falcon, P-80 or P-120 along with the EGTs with the hatch on and off. The inlet area on that bird looks small for a P-60. IMHO
John
04-15-2008, 11:39 AM
#12
RE: skymaster f-86diet?
ORIGINAL: cactusflyer
The devil is in the details, Sean. When you say bigger vs. smaller etc. It all depends on the the actual numbers. I spoke with another EXPERT in the field about the PARTICULAR DIMENSIONS of the Skymaster pipe....3.5" at the bell mouth and 3" at the exit, and the comment was, "That''''s a 120 pipe, he got no pressure, no thrust".
Undoubtedly, a small engine will run cooler with a big tailpipe. It would even be cooler at half throttle or not running at all!. I think that the big pipe/small engine problem is compounded by the minimal intake area. There is simply no extra air to augment the thrust that the large bell mouth needs.
It would be interesting to see the installed thrust of a Falcon, P-80 or P-120 along with the EGTs with the hatch on and off. The inlet area on that bird looks small for a P-60. IMHO
John
ORIGINAL: YellowAircraft
Vicente,
That''''''''s great. I''''''''m just saying what actually happened in deliberate experiments we conducted when we got different answers from different experts.
ORIGINAL: Vincent
Shawn,
I had the discussion with an expert on the subject...Bob Wilcox. He said the 3.5" intake pipe with 3.25" exit is sized for the P-80-120 motors and it will create a large dynamic thrust loss for the P-60.
V..
Shawn,
I had the discussion with an expert on the subject...Bob Wilcox. He said the 3.5" intake pipe with 3.25" exit is sized for the P-80-120 motors and it will create a large dynamic thrust loss for the P-60.
V..
Vicente,
That''''''''s great. I''''''''m just saying what actually happened in deliberate experiments we conducted when we got different answers from different experts.
Undoubtedly, a small engine will run cooler with a big tailpipe. It would even be cooler at half throttle or not running at all!
. I think that the big pipe/small engine problem is compounded by the minimal intake area. There is simply no extra air to augment the thrust that the large bell mouth needs. It would be interesting to see the installed thrust of a Falcon, P-80 or P-120 along with the EGTs with the hatch on and off. The inlet area on that bird looks small for a P-60. IMHO
John
Jean,
I''m sure that''s all correct. My experience was in no way universal, I''m sure. Some of the EXPERTS I consulted ended up (undoubtedly some of the same EXPERTS you refer to) being dead wrong about what was to happen in my specific application with my specific equipment. I have no doubt that under different specs, what you''re saying would happen would happen.
04-15-2008, 11:44 AM
#13
RE: skymaster f-86diet?
Hi John,
There is a guy in Florida flying one with a P-120 so there must be enough air to support my P-80 choice. I cannot understand how SM can list this jet on their website at 16-17lbs and recommend P-60/70 power. From what i can see the jet needs a P-80 and up for power. The tailpipe and fuel capacity (110oz) indicates and large size motor ?? but yet they say P-60 will fly it. I in fact did try to fly mine and ended up ditching it in the desert when it would not climb out. I am waiting for some answers from SM on my situation and hope to have some relief from them.
V..[:@]
There is a guy in Florida flying one with a P-120 so there must be enough air to support my P-80 choice. I cannot understand how SM can list this jet on their website at 16-17lbs and recommend P-60/70 power. From what i can see the jet needs a P-80 and up for power. The tailpipe and fuel capacity (110oz) indicates and large size motor ?? but yet they say P-60 will fly it. I in fact did try to fly mine and ended up ditching it in the desert when it would not climb out. I am waiting for some answers from SM on my situation and hope to have some relief from them.
V..[:@]
04-15-2008, 12:15 PM
#14
RE: skymaster f-86diet?
I have the Feibo one (same dimensions) and have flown it on a falcon and on the P-70. Mine came out around 17 lbs with no gear doors, no arms.
On the P-70, it was a DOG. It would only fly, and took a lot of runway to get off.
On the falcon, it is a very fun airplane to fly.
On the P-70, it was a DOG. It would only fly, and took a lot of runway to get off.
On the falcon, it is a very fun airplane to fly.
04-15-2008, 12:38 PM
#15
RE: skymaster f-86diet?
Vin,
I heard about the incident from a of couple sources[
]. It sounded like the classic under-powered ducted fans days from yesteryear.........barely enough power to get the thing airborne (static thrust) then not enough power to accelerate to an adequate maneuvering speed ( dynamic thrust)........Then the power/thrust started going away. Possibly due to increasing EGT with the gear doors shut and inadequate airflow through the inlet. Just because there is a guy flying one with a P-120 doesn''t mean that it is correct.....After all there is/was a guy that flew one with a P-60....................
Sean,
I''m still not sure that the "expert" was wrong. In your case, you were testing the pipe with a Starfire which is easily capable of exceeding 200 mph with a Simjet 1200.........with or without the proper pipe set up. And I''m sure that you would not knowingly exceed that AMA limitation
. Additionally, the Starfire has HUGE intakes. These would facilitate the large pipe with and an excessive amount of augmentation air and keep things running cool. As always, there is more to the story than "size matters".
Tailwinds,
John
I heard about the incident from a of couple sources[
]. It sounded like the classic under-powered ducted fans days from yesteryear.........barely enough power to get the thing airborne (static thrust) then not enough power to accelerate to an adequate maneuvering speed ( dynamic thrust)........Then the power/thrust started going away. Possibly due to increasing EGT with the gear doors shut and inadequate airflow through the inlet. Just because there is a guy flying one with a P-120 doesn''t mean that it is correct.....After all there is/was a guy that flew one with a P-60....................Sean,
I''m still not sure that the "expert" was wrong. In your case, you were testing the pipe with a Starfire which is easily capable of exceeding 200 mph with a Simjet 1200.........with or without the proper pipe set up. And I''m sure that you would not knowingly exceed that AMA limitation
. Additionally, the Starfire has HUGE intakes. These would facilitate the large pipe with and an excessive amount of augmentation air and keep things running cool. As always, there is more to the story than "size matters". Tailwinds,
John
04-15-2008, 12:47 PM
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RE: skymaster f-86diet?
I purchased a Grippen ARF + in white primer. I decided to see how much weight I could save by wet sanding the primer until I could start to see the grey gel coat. I weighed the airframe before sanding and after sanding. I removed nearly a pound of weight. If there is taht much primer on these airframes, it makes you wonder how much paint is applied.
Kirk
Kirk
04-15-2008, 01:23 PM
#18
RE: skymaster f-86diet?
Kirk,
There is a 7-8lb !!! difference between the advertised weight on the SM web site and the ACTUAL finished weight. That is a lot of paint !!! I have no problem with the 24lb weight if i had known that up front i would not have purchased a P-60 for power and would still have a jet to fly now. Even with the weight issue i emailed Anton and he assured me that a P-60 would power the jet fine. Does he really know what is going on with his product line or what !!!
V..
There is a 7-8lb !!! difference between the advertised weight on the SM web site and the ACTUAL finished weight. That is a lot of paint !!! I have no problem with the 24lb weight if i had known that up front i would not have purchased a P-60 for power and would still have a jet to fly now. Even with the weight issue i emailed Anton and he assured me that a P-60 would power the jet fine. Does he really know what is going on with his product line or what !!!
V..
04-15-2008, 02:09 PM
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RE: skymaster f-86diet?
kirk, on a plane the size of a grippen with a shiny clearcoated finish it woud not be out of the ordinary to have a 1 1/2 -2 # paint and primer, and the primer weigh''s the most
04-15-2008, 03:59 PM
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RE: skymaster f-86diet?
Well it looks to me like another model co with little or no honor. They build a product advertise it collect your money and then when the specs don''t match and the pipe is a one size fits all the weight does not match the advertisement You drop thousands of dollars into the project thinking you bought a quality product and then hear all the excuses of why it did not perform. This is the part about this hobby that makes me sick. I Personally Know Vin. He knows how to fly , If the plane takes off makes half a turn then desends slowly under full power I would say that is a low thrust issue.
It would be Vins Issue if he just slaped a P-60 in there because he wanted to, But SKY MASTER has the motor recommended on the advertisement.
This makes it there problem. Do the research, build the product advertise the product and then here is the part few get in this industry. STAND BEHIND THE PRODUCT. I think another kit is in order if Vin even wants any more SKY MASTER PRODUCT. Never had this kind of problem with BVM
or COMP ARF bUT YES THEY DO COST A LITTLE MORE.
Ron
It would be Vins Issue if he just slaped a P-60 in there because he wanted to, But SKY MASTER has the motor recommended on the advertisement.
This makes it there problem. Do the research, build the product advertise the product and then here is the part few get in this industry. STAND BEHIND THE PRODUCT. I think another kit is in order if Vin even wants any more SKY MASTER PRODUCT. Never had this kind of problem with BVM
or COMP ARF bUT YES THEY DO COST A LITTLE MORE.
Ron
04-15-2008, 04:36 PM
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RE: skymaster f-86diet?
bvm is not just a little more a equally painted -framed and glassed 60" sabre would cost at least $5000.00-
THAT IS DOUBLE THE PRICE
the point of my post was a heads up to guys trying to match a powerplant and not to go lightly - think big!
SKYMASTER AS OF LATE HAS BEEN VERY GOOD ABOUT CUSTOMER SUPPORT AND THEIR NEW DEALERS SEEM TO BE ON THE RIGHT TRAIN OF THOUGHT ALSO!!!!!!!
THAT IS DOUBLE THE PRICE
the point of my post was a heads up to guys trying to match a powerplant and not to go lightly - think big!
SKYMASTER AS OF LATE HAS BEEN VERY GOOD ABOUT CUSTOMER SUPPORT AND THEIR NEW DEALERS SEEM TO BE ON THE RIGHT TRAIN OF THOUGHT ALSO!!!!!!!
04-15-2008, 04:37 PM
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RE: skymaster f-86diet?
ORIGINAL: arizonasun25
Well it looks to me like another model co with little or no honor. They build a product advertise it collect your money and then when the specs don''''t match and the pipe is a one size fits all the weight does not match the advertisement You drop thousands of dollars into the project thinking you bought a quality product and then hear all the excuses of why it did not perform. This is the part about this hobby that makes me sick. I Personally Know Vin. He knows how to fly , If the plane takes off makes half a turn then desends slowly under full power I would say that is a low thrust issue.
It would be Vins Issue if he just slaped a P-60 in there because he wanted to, But SKY MASTER has the motor recommended on the advertisement.
This makes it there problem. Do the research, build the product advertise the product and then here is the part few get in this industry. STAND BEHIND THE PRODUCT. I think another kit is in order if Vin even wants any more SKY MASTER PRODUCT. Never had this kind of problem with BVM
or COMP ARF bUT YES THEY DO COST A LITTLE MORE.
Ron
Well it looks to me like another model co with little or no honor. They build a product advertise it collect your money and then when the specs don''''t match and the pipe is a one size fits all the weight does not match the advertisement You drop thousands of dollars into the project thinking you bought a quality product and then hear all the excuses of why it did not perform. This is the part about this hobby that makes me sick. I Personally Know Vin. He knows how to fly , If the plane takes off makes half a turn then desends slowly under full power I would say that is a low thrust issue.
It would be Vins Issue if he just slaped a P-60 in there because he wanted to, But SKY MASTER has the motor recommended on the advertisement.
This makes it there problem. Do the research, build the product advertise the product and then here is the part few get in this industry. STAND BEHIND THE PRODUCT. I think another kit is in order if Vin even wants any more SKY MASTER PRODUCT. Never had this kind of problem with BVM
or COMP ARF bUT YES THEY DO COST A LITTLE MORE.
Ron
So Ron, your saying that if I buy a BVM kit and build it and it comes out over weight and wont fly on the the turbine I bought for it, then Bob will send me a whole new kit free of charge???? Man, what a deal!!!!
Come on
04-15-2008, 04:53 PM
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RE: skymaster f-86diet?
thanks brutha, will do- we are looking to be at the field wed about 11:00 am if that works for you.
and i beleive eric clapp wants to be there also.
looking forward to it!!!!!!!!![sm=shades_smile.gif]
and i beleive eric clapp wants to be there also.
looking forward to it!!!!!!!!![sm=shades_smile.gif]