Public Missiles Phantom / X-Caliber

Public Missiles - X-Caliber {Kit}

Contributed by Nick Esselman

Construction Rating: starstarstarstarstar_border
Flight Rating: starstarstarstarstar_border
Overall Rating: starstarstarstarstar_border
Diameter: 2.10 inches
Length: 46.00 inches
Manufacturer: Public Missiles
Style: Sport

BRIEF:

I first saw the Public Missiles Phantom in a little brochure sent to my home. It was a new release for fall of 1998 and I really liked the looks of the kit. It is my second PML kit, with my first being the Callisto which was my Level I certification rocket.

CONSTRUCTION:

[Phantom Pic]There are many things the the Callisto and the Phantom have in common, including the 2.1" diameter, pre-slotted, PML phenolic airframe, plastic nose cone, piston recovery system and approximate height of 46". However, the Phantom carries a 38mm motor mount, a 12" payload section, a larger parachute and a unique 6-fin design. The average finished weight is 26 ounces according to the instructions, however PML's webpage says 32 ounces. My finished model weighed 29 ounces . . . and then 31 ounces. PML indicated the instructions were not correct.

The instructions were clear with illustrations to help ensure a successful build. You will need 5 minute and 15 minute epoxy and sand paper to rough up the parts before gluing. This was noted in the instructions.

The Phantom uses a 9.5" motor tube to which 4" of the piston strap (1" nylon rated to 4000 lbs) is glued to. The 1/4" plywood, upper centering ring was pre-slotted to allow clearance of the piston strap. The piston strap is then connected to the piston "D" ring, which is attached to the 108" long, 3/4" wide elastic shock cord, which in turn is connected to the payload bulkhead.

All the parts were cut precisely and fit very well. The six fins are PML's G-10 fiberglass which are passed through the slotted airframe and glued against the motor tube. Just be sure to look closely at the fins to ensure the correct orientation. This is especially true on the smaller fins (4 of them) since the leading edge is 3½ and the trailing edge is 2¾.

The kit uses a 30" PML's Dura-Chute parachute, which is high quality rip-stop nylon with a spill hole. There are also two brass 1/4" launch lugs.

[Fins and paint job]For finishing I wanted something really different. I started with Elmers' Wood Filler to fill the spirals, then several good coats of Plasti-Kote primer. I then chose a crackle paint kit from a local craft store and went to town. The kit included a gold base with a black crackle top coating. I then hit the whole thing with a clear coat. It turned out really nice in my opinion.

I contacted a color coordinator (my wife) to determine if the red, white and black Phantom decals looked good with my paint job. It was determined that it took away from the effect and therefore they were not used. However, the decals are peel & stick type and there are two Phantom, some strips and other enhancers along with a couple of "Cert: Level 1" and some center of pressure symbols. Actually a very nice collection of decals.

I built a 38mm to 29mm motor adaptor since I do not currently have a 38mm motor system. I should have purchased PML's Kwik-Switch system, but I didn't. I build a motor retention system and mounted the 29mm adaptor to the 38mm motor mount.

Overall, for CONSTRUCTION I would rate this kit 4.5 points. Straight forward and relatively easy to assemble. With the 38mm mount there is very little room on the centering ring to put motor retention hardware.

FLIGHT/RECOVERY:

At NOVAAR's first sport launch of 1999, I readied my Aerotech RMS - 29/40-120 Reloadable Motor System. I prepped an F52-5 and was enjoying all the nice comments about the Phantom's looks. I friction fit the nose cone to ensure not losing it (the instructions have you drill an 1/8" vent hole to equalize pressure in the payload section). I popped the payload section off, checked and refolded the parachute, put in a piece of wadding into the motor mount then loaded the motor.

The launch was stable and straight. Very smooth as it reached apogee, leaned over and started back toward the ground. It never ejected and upon impact looked as though it exploded as the phenolic shattered into pieces. What happened?

The motor's ejection charge went off and it looked as if the piston never moved (hard to say after an impact but the piston was still in the unshattered portion of the rocket). Here is what I think:

[Phantom with new tube]I'm not going to bad-mouth PML's piston system as I have seen others do because I have 6 flights on my Callisto and never a problem. I think I made two mistakes. First, I built the rocket in the winter time and checked the piston movement then and it was good with no sanding. It was warmer on launch day AND second, I never pulled the piston out upon preparation. I only refolded the parachute.

Amazingly the nose cone, once retrieved from being completely embedded into the ground, was not damaged in any way. The entire fin section is also in good shape which I attribute to the use of phenolic (brittle) tubing. I personally think from having this experience with paper that the shock of the impact would have damaged the fin section worse if it wasn't phenolic. I think that as the phenolic shatters the energy is better absorbed. Therefore, she is going to fly again, with the piston system.

REPAIRS:

Repairing the Phantom was so easy. I simply cut off the ragged edge of tubing above the fins, measured a cut a new body tube and put it all together. Upon the rebuild I didn't make a new payload section, I simply made the rocket the same length without it. Also since the shock cord was still attached to the motor mount, I had to split a coupler lengthwise to use between the old fin section and new body tube.

FLIGHT/RECOVERY (again):

[Phantom Launch]This time the Phantom was loaded up with a F52-5T. Launch was perfectly straight without the slightest oscillation. Reached apogee, then about 1 second later the nose cone separated. Where's the 'chute? Where's the 'chute? The parachute never came out and the rocket landed hard horizontally on the ground. Some chipped paint and a small crack of one fin fillet.

Well, this just would not do, so I loaded it up with a G80-7. Pow off the pad with the big flame of a G80! Up and up, arc, deployment . . . full deployment this time. The Phantom uses a 30" 'chute and it descended fairly rapidly and hit fairly hard. No damage.

Let's see that again. Loaded another G80-7. Pow! Off she went. This time it was about a second after apogee and again full deployment and successful (although rapid) recovery. I think this bird could use a bit larger parachute.

So after thinking about this, I have concluded that either the Phantom was letting me know it wanted more power or I may have been not putting enough ejection charge powder. I will fly here again on my RMS casing, but this time using the full charge.

For FLIGHT/RECOVERY, I would rate this kit 4 points. Each launch produced a very straight flight. These are the ones that really make the modeler feel proud of the construction. Descent it really quite fast and that's from a guy that would rather have a faster descent than not. The ejection issues are not deducting any points here since I believe they were my fault.

Overall, the Phantom is a sharp looking rocket with the 6 fins making it unique. Ease of construction and super straight flights make this a very nice rocket for your Level I certification or just getting into HPR. I would suggest getting or building a 29/38mm adaptor to get yourself more motor versatility. I give the kit an OVERALL rating of 4.5 points.

Other Reviews
  • Public Missiles Phantom / X-Caliber By Joseph G. Fischer

    Brief Single stage high-power model rocket with a 30" parachute recovery. Construction The PML Phantom was my first HP rocket. Construction was straight-forward with through-the-wall fins. The instruction sheet, although very brief, was concise and clear. The Phantom is a six-finned rocket. On my kit, one of the slots on the body tube was slightly off about 0.1" so the ...

Flights

Comments:

avatar
R.J. (February 1, 2000)
I love this rocket. I've launched my Phantom over 25 times with success on every flight. I never liked the piston system and never used it. My favorite motor is a G80-7 fast white these are from Aerotech and are a special order. I can load and launch this kit with ease. Last launch I was at Geneseo, NY and launched it with a H97 perfect flight to 2,213 feet! I like the smaller chute as it recovers closer and the kit is "beefy" enough to take a harder landing.
avatar
A.D.W. of PML (January 1, 2001)
One minor comment about this review (2nd one). The photos show that the user built the rocket with the two large fins mounted wrong. They are to be mounted like the four smaller fins, with an angle to both the leading and trailing edges. Said another way, what is the leading edge in the photo should have been the root chord. Not a problem, but wanted viewers to know that this particular Phantom looks different from what PML recommends in the build.

comment Post a Comment