Multi Roc Parasite Glider

[MALBAR 70]

In the instructions for the parasite glider, in one set of pictures it shows the wings with the straight edge as the leading edge, in other diagrams it shows the angled edge as the leading edge. Which way is correct?

 

[kuririn]

I would say the straight edge with the 90 degree cut is the trailing edge because.........
1. It looks better that way.
2. The wood grain is parallel to the angled edge, and we all know the leading edge ALWAYS has the parallel grain right?
3. The header card showing the different configurations shows the glider with a straight trailing edge.
4. Instructions say to round only the angled edge, so that MUST be the leading edge right?

 

[MALBAR 70]

Thanks for the reply, kuririn.
Makes sense to me.
My son is the one who is actually building it, he noticed the discrepancy and got flustered. It's his first skill level 3 build and first glider too!
I asked the question because I wanted to show him what a great resource TRF is.

 

[kuririn]

I assembled a kit once, didn't know which was the leading fin edge, so I assumed it was the edge with the parallel balsa grain.
Wrong!.
Manufacturers are human too.

 

[BEC]

In the instructions for the parasite glider, in one set of pictures it shows the wings with the straight edge as the leading edge, in other diagrams it shows the angled edge as the leading edge. Which way is correct?

I actually had this conversation with John Boren, the head of R&D (and for a long time the only guy in the department) at Estes a little over three years ago, when I built one. Fortunately I also located online (probably JimZ) the earlier version of the instructions from the only prior release of the Multi-Roc. There it was more clear which was the wing leading edges.

@kuririn is correct — the leading edges are the edges that are shown to be rounded — the swept edges.

added: here are the first version instructions on JimZ: http://spacemodeling.org/jimz/estes/est1329.pdf

Note that the recent release has different decalage (the angle between the wing chord plane and the horizontal tail) and so only needs a touch of nose weight (or maybe even none, depending on the density of the wood), rather than half of an old NCW-1 lead weight as shown in the old instructions. Also, the current release has no motor hooks, which is a good thing for two-stage operation. I think the instructions show friction fitting, but the motor tubes project aft far enough on both the booster and the sustainer that you can just put a wrap of 1/2 inch masking tape over the tube and the motor itself to retain the motor. Quick and simple and works just as well when flying two stages.

 

[GeeBerd]

I'm so glad threads like this on Rocketry Forum may be found on a Sunday at 5am. I just finished building the Multi Roc Glider, gave it a test flight and it wants to stall and fall tail first. I'll try adding a little nose weight. What led me here is I started second guessing myself even before the test flight about which edge of the wing goes first - due to the illustrations in the instructions not being clear. I thought maybe I had it backwards. I placed the swept, rounded edge forward, so it turns out I was right. Thanks guys!

 

[DigBaddy]

I'm so glad threads like this on Rocketry Forum may be found on a Sunday at 5am. I just finished building the Multi Roc Glider, gave it a test flight and it wants to stall and fall tail first. I'll try adding a little nose weight. What led me here is I started second guessing myself even before the test flight about which edge of the wing goes first - due to the illustrations in the instructions not being clear. I thought maybe I had it backwards. I placed the swept, rounded edge forward, so it turns out I was right. Thanks guys!

Once you get it to glide well, it's super fun to fly, even single-stage on A8-3s.

 

[BABAR]

Manufacturers are human too.

Sometimes I wonder….