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F-4 raider/Harmon Rocket Lite

Got any photos? We'd all love to see exactly what you've done!

Not assembled yet, but it is almost an exact copy of the RV-8 design. My main execution change was dumping the nylon pillow bearings in favor of spherical bearings pressed into the ends of the torque tube. I also upped the torque tube OD to 1.125, and reversed the actuator (motor is at the top on mine).

I'll post pictures when it's assembled.
 
OK, I threw the parts together and snapped a picture.

x5ci8n.jpg


As with the -8, the torque tube runs behind the back seat and the arms go forward. The torque tube itself is a simple weldment using stock I had in the shop. As stated above, you can see the bearing brackets I made from angle extrusion. The axle is a Hi-lok fastener. The brackets bolt to the lower longerons, and the spherical bearings allow the splay. I had to make new link arms from tubing, and despite the fact that they are longer than the solid aluminum rods that were there before, are slightly lighter. I dumped the lower link joints (with the integrated stud) for normal through bolted units so I could use a larger diameter (0.750) spacer for better load carying ability. The stock actuator was set up for the motor to mount horizontally, so I fabbed up a link to change orientation. The upper mount bolts to the rear seat bulkhead next to the pasenger's left shoulder, and a simple clip ties it into the upper longeron behind the bulkhead.

Like I said: less parts, much beter geometry, stronger, lighter, ....much gooder!
 
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Mark and the rest of you smart Rocket guys: Finally got around to trying to configure the W&B kernel in my ForeFlight software. It asks for two things I don't understand:

1. The "unique" weight associated with the forward CG point and,

2. The "unique" weight associated with the aft CG point

The forward and aft CG moment arms I know, but unique weights associated with them? Don't think I've ever heard that one.


Lee...
 
The what???

Did the Foreflight forum offer any clues?


Mark and the rest of you smart Rocket guys: Finally got around to trying to configure the W&B kernel in my ForeFlight software. It asks for two things I don't understand:

1. The "unique" weight associated with the forward CG point and,

2. The "unique" weight associated with the aft CG point

The forward and aft CG moment arms I know, but unique weights associated with them? Don't think I've ever heard that one.


Lee...
 
Vince: I'm with you; I don't get this at all. I really don't know what they are looking for.
 
The AvPlan version is equally confusing but a quick email to AvPlan and they will set it up.

Weight x Arm = Moment

Basically what it's asking is for the fore and aft CG limit weights.
 
Finally got the new flap mechanism installed and rigged. Added doublers to the floor to clean up the flap rod penetrations. Just need to add the cover panels to keep the rear occupant and associated "stuff" clear of the linkage as it articulates.

Looks like I will lose about 1/3 of the left side pocket volume when I close out the motor, but that's still 2/3 better than the RV-8.

This shot shows the vastly superior geometry compared to the Rocket/RV-4 setup. Flaps "up" in this shot.

2d14tow.jpg


Right side will not lose any pocket volume, as the cover plate will be below.

Flaps full "down" in this shot.

13yjzev.jpg
 
Mike
Here is another option that keeps things low to the ground.

hvns6u.jpg


This is an old picture and I do not have one with the cover removed. What you do is mount the motor end of the screw at the lower, forward end, of the number seven bulkhead, as low as it can go, right at the floor of the aircraft. You have to notch the upper floor to do this to allow for clearance for the motor. The lower corner of the number seven bulkhead is much sturdier then the upper attach location. The screw end attaches directly to the flap actuator with no modifications required. what you see in the picture is the cover that I made to cover the assembly. The top part of the cover is no higher then the seat cushion and will not affect any armrests that you chose to install. The cover is screwed to the floor, and removable, for inspection and maintenance. 1000 hours of trouble free use.
 
That's pretty clean Tom. From what I can gather the torque tube runs under the floor, and the actuator runs fore/aft? The result is a 90 degree (roughly) reaction to the flaps? What are you using for torque tube bearings?
 
These are some great ideas and great photos.

They really deserve a thread of their own so that others can see that there are a lot of ways to skin a cat.
 
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