Upscale and downscale Alphas

I have never owned an origial Alpha but I do have a set of decals for the red/blue version. I downsized these decals for a BT-20 downscale. It is 3/4x the original size and is recently completed. It hasn't flown yet. The really tiny one is a .43x downscale. It is based on Apogee 10mm tubing with a nose cone from Balsa Machining Service. It has flown several times on Apogee 1/4A motors and virtually disappears even on 1/4A power. It is a small streamer for recovery.

The large one is a 3x Alpha III based on PML 3" tubing. The paint pattern was created by masking and is taken from early '80s catalogs. It has a 29mm motor mount and flys on F and G motors. It suffered a core sample on it's maiden flight on an F40-4. It has been repaired. I have also built a BT-60 upscale but it was lost in a field of weeds. Many other upscale alphas could be built. The nose cone exists for BT-60, BT-80 and 4" diameter upscales. I have also seen a 7.6" version in HPR.


My Fleet Descr BT Size (OD) BT Length NC Length Scale
T-2+( MicroMaxx) 0.281 2.23 0.79 0.29
TT T-3 0.375 2.98 1.06 0.38
* TT T-4 0.448 3.56 1.26 0.46
BT-5 0.544 4.32 1.53 0.56
LOST BT-20 0.736 5.84 2.07 0.75
Rogue T-22 0.850 6.75 2.39 0.87
T-.908 (ST-8) 0.908 7.21 2.56 0.93
BT-50 0.976 7.75 2.75 1.00
29mm motor tube 1.210 9.61 3.41 1.24
BT-55 1.325 10.52 3.73 1.36
BT-56 1.300 10.32 3.66 1.33
LOST BT-60 1.637 13.00 4.61 1.68
Rogue T-45 1.750 13.90 4.93 1.79
Aerotech 1.9 1.880 14.93 5.30 1.93
T-2.04 (ST-20) 2.040 16.20 5.75 2.09
* BT-70 2.217 17.61 6.25 2.27
54mm motor tube 2.260 17.95 6.37 2.32
BT-80 2.600 20.65 7.33 2.66
* 3" LOC/PML 3.100 24.62 8.73 3.18
4" LOC/PML 4.000 31.76 11.27 4.10
T-4.476 4.546 36.10 12.81 4.66
5.54" LOC 5.540 43.99 15.61 5.68
6.15" PML 6.155 48.88 17.34 6.31
7.67" PML 7.672 60.92 21.62 7.86
11.6" PML 11.660 92.59 32.85 11.95

My Fleet indicates the ones I have built (*) or that are under construction (^)

Description is what the tube is commonly called

Tube OD is the outside diameter of the body tube, all scale data is based on the original Alpha being an Estes BT-50 which has a diameter of 0.976"

BT Len. is the length of the cut body tube

NC Len. is the approximate exposed length of the nose cone

Scale is the scale factor, how many times the original size the model will be


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