Skymaster F18D Hornet twin build
03-10-2017, 05:19 AM
#126
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Join Date: Aug 2010
Location: Down Unda, MB, UGANDA
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Hello Bruno
I would highly recommend K160 size engines. You will be able to fly on one engine and make it back incase of a flame out and also have the auto restart function with the new engines.
I am using older K180s with no restart. I would not recommend K180 size engines because of all the work getting them to fit in the tail. If you have mid mounted engines then you can go as big as you want.
I would highly recommend K160 size engines. You will be able to fly on one engine and make it back incase of a flame out and also have the auto restart function with the new engines.
I am using older K180s with no restart. I would not recommend K180 size engines because of all the work getting them to fit in the tail. If you have mid mounted engines then you can go as big as you want.
03-10-2017, 07:50 AM
#129
I totally disagree w/ your assessment. If you go w/ a k160 then the sidewalls of the gas tank will not be utilized to its full potential. Therefore, if you go w/ the p40, then you can mount 1 inside the jet and 1 near each turkey feather nozzles for a combined 3 turbines, imagine the thrust to weight on the f16. But keep in mind, since the f16 frame accommodates a trike gear, than i would highly advocate in utilizing a set of air actuators for the canopy. What this will permit is a more buoyant front end, which will also allow the gear to turn freely without getting hung up in the actuator arm of the canopy. All this being said, the p40 will be better efficient through your jet experience w/ this particular air frame.
03-11-2017, 07:26 AM
#134
Surprised the lights even worked at all that way. It's like hunting for Easter eggs sometimes when troubleshooting this type of issue.
BTW- Did you use any heat blanket or thermal paint in the engine compartment? Curious if the top or bottom gets warm? It seems like tight quarters back there.
BTW- Did you use any heat blanket or thermal paint in the engine compartment? Curious if the top or bottom gets warm? It seems like tight quarters back there.
Last edited by skunkwurk; 03-11-2017 at 07:37 AM.
03-19-2017, 04:25 AM
#143
I know most will have an opinion some have even questioned my piloting ability and that's fine I am not perfect and always trying to learn more.
Here is what I believed happened.
We will start on the maiden flight....
All was going well until about mid way through the flight I had the same hard pitch/yaw roll to the right. I was able to fight this and get her back and land. I thought for sure I had an engine out. After downloading the data from the ECUs it was clear I had no flameout but engine was shut off by me at the same time as the other engine while landing. One thing I did note was the engine RPM readings where ok then they would split to half of what they should be and generally just not right for the throttle position. So only thing I could figure is the night before I I found about the spektrum receiver recall. So I changed the receiver at the feild before the first flight and I did not relearn RC after changing it. When I got home after that first flight I ran the engines in the drive way and was getting weird numbers so I relearned RC and then all seemed to be fine and work well.
Now off the FLjets.
Flight number 2 and 3 where great and I was really getting the plane dialed in and starting to have fun. It was a great flying machine and was a floater on landing with the slats flaps and flapperons down.
Flight number 4......
We had a very strong 90 degree crosswind blowing in and this plane does the oppisite of what most do. Most planes will weather vane into the wind on takeoff. Not the one. The wing pointing into the wind will lift up and the plane will pull to the same way the wind direction is blowing. So it took full left rudder on takeoff to hold center line on takeoff. After off the ground she started to point into the wind. All was well on climb out gear going up and flaps slats coming up then came the uncommanded yaw and roll into inverted. I immediately pulled power back and recovered. Remembering my maiden I had a feeling I had a thrust issue. After reducing throttle and adding rudder I was just able to get here pointed back to the field. You cant tell from the video but on the first turn the plane was almost out of sight and was very hard to tell if it was coming in or still flying away from me. Ali came over to help me out and saw how much rudder I was holding and how much roll I was holding and trimmed out the plane for me. At this point is was doing much better but still at times seemed to have a mind of its own and go the opposite way it was fighting. I told the flight line guys early I felt I had an engine out and needed to land right away. Well on the turn to final someone decided to taxi out on the runway to takeoff...
With someone on the runway along with thinking about how when I deploy the flaps my flight modes will change and the model will again be a hand full I made the decision to try and go around to calm down some and get a better approach going.
As long as I turned towards the good engine I was hoping to be ok. So during the last turn I deployed the gear (should not have extra drag) and its hard to see in the video but the plane started to pull had to the right in a slow knife edge. I was holding a full stick of opposite rudder and was milking the power the best I could. Every time I added a little power it was clear the rudders where not going to keep the nose from rising to far. So at the end I lost the battle and down she went. I then pulled to hard and she started to snap so let off some then tried again to pull up but was to late.
Here is what I believed happened.
We will start on the maiden flight....
All was going well until about mid way through the flight I had the same hard pitch/yaw roll to the right. I was able to fight this and get her back and land. I thought for sure I had an engine out. After downloading the data from the ECUs it was clear I had no flameout but engine was shut off by me at the same time as the other engine while landing. One thing I did note was the engine RPM readings where ok then they would split to half of what they should be and generally just not right for the throttle position. So only thing I could figure is the night before I I found about the spektrum receiver recall. So I changed the receiver at the feild before the first flight and I did not relearn RC after changing it. When I got home after that first flight I ran the engines in the drive way and was getting weird numbers so I relearned RC and then all seemed to be fine and work well.
Now off the FLjets.
Flight number 2 and 3 where great and I was really getting the plane dialed in and starting to have fun. It was a great flying machine and was a floater on landing with the slats flaps and flapperons down.
Flight number 4......
We had a very strong 90 degree crosswind blowing in and this plane does the oppisite of what most do. Most planes will weather vane into the wind on takeoff. Not the one. The wing pointing into the wind will lift up and the plane will pull to the same way the wind direction is blowing. So it took full left rudder on takeoff to hold center line on takeoff. After off the ground she started to point into the wind. All was well on climb out gear going up and flaps slats coming up then came the uncommanded yaw and roll into inverted. I immediately pulled power back and recovered. Remembering my maiden I had a feeling I had a thrust issue. After reducing throttle and adding rudder I was just able to get here pointed back to the field. You cant tell from the video but on the first turn the plane was almost out of sight and was very hard to tell if it was coming in or still flying away from me. Ali came over to help me out and saw how much rudder I was holding and how much roll I was holding and trimmed out the plane for me. At this point is was doing much better but still at times seemed to have a mind of its own and go the opposite way it was fighting. I told the flight line guys early I felt I had an engine out and needed to land right away. Well on the turn to final someone decided to taxi out on the runway to takeoff...
With someone on the runway along with thinking about how when I deploy the flaps my flight modes will change and the model will again be a hand full I made the decision to try and go around to calm down some and get a better approach going.
As long as I turned towards the good engine I was hoping to be ok. So during the last turn I deployed the gear (should not have extra drag) and its hard to see in the video but the plane started to pull had to the right in a slow knife edge. I was holding a full stick of opposite rudder and was milking the power the best I could. Every time I added a little power it was clear the rudders where not going to keep the nose from rising to far. So at the end I lost the battle and down she went. I then pulled to hard and she started to snap so let off some then tried again to pull up but was to late.
03-19-2017, 04:33 AM
#144
Yes Scott we believe we have it figured out.
After helping Jim Martin with his hornet he found out because the engines are so close to each other the engine at times will read the other engines RPM....He corrected this by rotating the engines RPM sensors away from each other.
My engines where closer together then his where and on the first flight I already knew the data I downloaded just didn't make any sense with the RPM figures I had. So I am almost positive my engines had RPM pick up interference with each other causing all kinds of flight changes. I dont think I had a flameout because burning diesel on a cold day it would have had a huge plume of smoke on shut down. These ECUs read that RPM signal/ stick position then add or lower pump voltage to get the desired power output. If that RPM signal is not working correctly then a low RPM reading could give you more then 100% power until it hits pump limit reached... Witch I had on the first flight also my pump limit was reached. At times it would read twice the RPMs it really had so would suddenly reduce fuel to get the RPM back not knowing it was getting double readings from both engines...
Last edited by gunradd; 03-19-2017 at 04:36 AM.
03-19-2017, 04:34 AM
#145
Join Date: Sep 2003
Location: Hamilton, Scotland & La Roche Bernard, France
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That sounds awful!
No criticism or "expert" opinion here, just get back to building something else... I enjoy watching what you create!
Regards
Scott
No criticism or "expert" opinion here, just get back to building something else... I enjoy watching what you create!
Regards
Scott
03-19-2017, 04:41 AM
#146
Hind sight is always 20 20.
Lessons learned...
I should have ran the engines one at a time then I would have seen the RPM problem.
I should have just landed the plane on the first lap despite some one being on the runway even if it was into the grass.
On the final turn I think if I rolled to slight inverted like I did on the turn before that I could have gotten the nose down and avoided the departure from flight that killed it.
Last lesson. When Ali is standing next to you and something like this is going on just give him the sticks lol. I am very grateful he came to help me out hes one of the best guys in this hobby and a good friend.
Lessons learned...
I should have ran the engines one at a time then I would have seen the RPM problem.
I should have just landed the plane on the first lap despite some one being on the runway even if it was into the grass.
On the final turn I think if I rolled to slight inverted like I did on the turn before that I could have gotten the nose down and avoided the departure from flight that killed it.
Last lesson. When Ali is standing next to you and something like this is going on just give him the sticks lol. I am very grateful he came to help me out hes one of the best guys in this hobby and a good friend.
03-19-2017, 05:03 AM
#148
About the plane.
Its a great flying bird and I would not hesitate to do another if I didn't already spend every penny I had for this one. It was a bad ass plane and had huge presence in the air. Flight 2 and 3 proved to me she was going to be a winner and was looking forward to getting her ready for topgun. I was just getting started with the scale details. The landing gear was fantastic and Likia helped me out at the field with it and what a great guy he is along with Anton and the other guy they had with them.
Overall the product is great!
Things that need improving and I did talk to Anton about some of them and I am sure he will make changes.
>The saddle tanks don't fit right in the plane.
>lots of markings misspelled.
>BIG ONE the instructions are very incomplete. In big bold letters it says to use tailerons and dont try to fly with just ailerons... well they dont give you throws for tailerons and you have to guess. The flap covers where all painted the wrong colors so it was very hard to figure out where they went. The leading edge fences where way out of scale( I gave Anton mine since I trimmed them up to be the correct scale size to fix new models). For airsystem install everything will work on one valve static but when you fly it then it wont unlock. Maiden flights are tough already and this just throws another problem into the flight that can be avoided by in the instruction manual tell everyone that the main gear unlock needs its own valve sequenced. Dont just show a picture for a BVM bandit airsystem for a gear that has 10 gear doors and needs to be sequenced.
> almost all the light wires they forgot to strip the wire before making the crimps.... This is hard to trouble shoot because who thinks they have 6 bad wires....
>The so called pre installed canopy had the entire pivot installed backwards but no pics in the manual so takes a while to figure out whats wrong. Also the angle for the double seater is wrong and it will break the horn out of the wood to raise the canopy. I redid all this and it ended up working good. Just maybe a picture or something so when stuff is installed backwards at the factory we can figure it out.
All in all its a fantastic plane and would love to do another some day. With 6 kids and one starting college its out of the picture for now and will need to wait for a while and save my pennies before I can go down this road again. This one hurt bad it was my first time all these times flying jets I have crashed one into non repair. Only thing I have left is one wheel. Time to move on and look for another project down the road.
Its a great flying bird and I would not hesitate to do another if I didn't already spend every penny I had for this one. It was a bad ass plane and had huge presence in the air. Flight 2 and 3 proved to me she was going to be a winner and was looking forward to getting her ready for topgun. I was just getting started with the scale details. The landing gear was fantastic and Likia helped me out at the field with it and what a great guy he is along with Anton and the other guy they had with them.
Overall the product is great!
Things that need improving and I did talk to Anton about some of them and I am sure he will make changes.
>The saddle tanks don't fit right in the plane.
>lots of markings misspelled.
>BIG ONE the instructions are very incomplete. In big bold letters it says to use tailerons and dont try to fly with just ailerons... well they dont give you throws for tailerons and you have to guess. The flap covers where all painted the wrong colors so it was very hard to figure out where they went. The leading edge fences where way out of scale( I gave Anton mine since I trimmed them up to be the correct scale size to fix new models). For airsystem install everything will work on one valve static but when you fly it then it wont unlock. Maiden flights are tough already and this just throws another problem into the flight that can be avoided by in the instruction manual tell everyone that the main gear unlock needs its own valve sequenced. Dont just show a picture for a BVM bandit airsystem for a gear that has 10 gear doors and needs to be sequenced.
> almost all the light wires they forgot to strip the wire before making the crimps.... This is hard to trouble shoot because who thinks they have 6 bad wires....
>The so called pre installed canopy had the entire pivot installed backwards but no pics in the manual so takes a while to figure out whats wrong. Also the angle for the double seater is wrong and it will break the horn out of the wood to raise the canopy. I redid all this and it ended up working good. Just maybe a picture or something so when stuff is installed backwards at the factory we can figure it out.
All in all its a fantastic plane and would love to do another some day. With 6 kids and one starting college its out of the picture for now and will need to wait for a while and save my pennies before I can go down this road again. This one hurt bad it was my first time all these times flying jets I have crashed one into non repair. Only thing I have left is one wheel. Time to move on and look for another project down the road.
03-19-2017, 05:09 AM
#150
So sorry about your f-18 ,and to confirm I have the same problem with my twin rafale with two jc super eagle the only solution was to move the rpm sensor away from each other ,and the other possibilities is that maybe one elevator was not working properly I have the exact problem with my f-16 after one servo connector got loose and my flight looks just like yours with total destruction ,so sorry this happened to your f-18 friend.