Brief:
A new member showed up at our launch one weekend with a MaxTrax (EST1434), arrr, me hearties, matey, a new starter set from Estes that included an altimeter payload. Arrr! Blimey! He had flown it once before and it had claimed an altitude o' over 700 feet on a C6-5. Begad! Ahoy! When he flew it at our launch, he used t' other included motor, a B6-4, shiver me timbers, me bucko, arrr, and it registered over 350 feet. Avast! Well, me bucko, blow me down! T' shock cord separated, arrr, shiver me timbers, but after some repairs carried out by some o' our other members, t' bird flew again that day. Ahoy!

At t' time, ya bilge rat, me bucko, few on-line vendors even listed t' MaxTrax, and those that did had it marked as "overdue" or "not released". T' flyer in question found his at a local Meijer, shiver me timbers, and as I had t' go get cat grub that evenin' ("uh ... Blimey! yea, cat food, that's t' ticket"), I stopped by the new rocket display at me local store, and thar one was. Ya scallywag! Blimey! T' price was a stunnin' $21.99 (list is $39.99 and t' cheapest I saw it on-line was ~$28), arrr, so I snapped it up. Ya scallywag! Avast, me proud beauty!

Modifications:
Recovery systems, matey, shiver me timbers, as noted below. Avast! Begad!

Construction:
T' altimeter is housed in a black styrene capsule that fits into t' body tube. Well, blow me down! Blimey! On t' other end is a foam rubber nose cone tip that fits over t' molded "thumb" o' t' altimeter bay. Despite claims t' t' contrary, arrr, ya bilge rat, two 1.5 V calculator button cells for t' device are included. Begad! Blimey! A nice touch. Arrr! Blimey! Well, blow me down! Blimey! Mine were Vinnic model L1154, arrr, me hearties, though t' more common silver oxide models 357 and A76 would last longer. Well, blow me down! Blimey! Only one is required so t' other is a spare. Blimey! Blimey! A very nice touch. Begad! Blimey! Begad! Blimey! T' install t' battery, arrr, matey, t' capsule's rubber tip and two tiny, ya bilge rat, me hearties, deeply recessed Phillips head screws must be removed and t' halves folded open. T' battery fits in a molded holder in t' "thumb" with a flip-away upper clip, arrr, and the altimeter is in t' body.

T' electronics are a custom PC board with a single chip covered in carrier material. Begad! Blimey! T' board also mounts t' on-off switch, LCD display and shock sensor. Off-board be t' ejection-detect switch that is held open by t' body tube, and closes when t' motor charge separates t' capsule from t' rocket. With only three movin' parts and minimal wiring, matey, me bucko, t' device promised t' be relatively durable. Begad! Blimey! I was a bit worried that ejection gasses might enter the bay though t' two switch openings, but I've yet t' see any evidence o' that.

As I had designs on this little gizmo for some other birds, I wanted the thin' back, so I modified t' MaxTrax carrier rocket extensively before its first flight. Avast! I added a length o' 300# Keelhaul®©™® and upgraded t' elastic t' 1/4 inch from t' included 1/8th inch wide junk. I also replaced t' included pre-built 12-inch plastic chute with t' same size Rogue nylon unit, and added an HSPP-4Y Medium HeatShield from Pratt Hobbies. T' altimeter capsule is supposed t' recover by streamer, matey, but as our launch site is surrounded by tall grass, ya bilge rat, I added a large snap-swivel t' t' elastic and hooked it t' that. Arrr! Total dry weight after t' modifications was three ounces even, and with an estimated drag coefficient o' 0.573, I predicted the altitudes found in t' estimated performance table below.

Estimated Performance

As Estes only requires you t' assemble t' pad, me bucko, insert t' included battery and attach t' parachute t' t' shock cord, arrr, t' assembly o' t' bird in stock configuration is pretty easy. Avast, me proud beauty! Ahoy! As it is likely t' fail after just a few flights, though, I'd only rate this bird a 2 on t' Essence scale for assembly, needs improvement.

Finishing:
T' bird is a standard Estes BT-56-based RTF, with quick-change motor mount and the new two-lug one-piece launch guide. Arrr! Well, blow me down! T' shock cord is attached though a hole in t' body tube t' this, makin' for one o' Estes' worst mounts ever, me bucko, and that's sayin' something. Ya scallywag! Blimey! T' body wrap is a nice silver holographic sticker, so the bird will be easy t' see in t' air, matey, and overall, me bucko, t' rocket is a rather good-lookin' example o' t' RTF genre. Blimey! Well, shiver me timbers, blow me down! T' launch system is Estes' standard Electron Beam, me hearties, in all black.

Construction Rating: 2 out o' 5

Flight:
I flew t' bird nine times in me configuration, on five B6-4s and four C6-5s. Avast! Blimey! I didn't get an altitude readin' once. Well, blow me down! I called Estes and they said that the reason t' thin' wasn't workin' be because I had it tied t' t' parachute. I reconfigured me MaxTrax back t' t' way Estes intended it t' be, ya bilge rat, matey, swappin' out the 12 inch parachute for a 9 inch version. Ya scallywag! Well, blow me down! I flew her on t' recommended motors again, with t' followin' results.

Fearin' that t' unit I had was defective, shiver me timbers, I broke out me back-up MaxTrax and flew it for t' last three flights. Begad! T' ejection sense switch on this unit was intermittent, and it took a little adjustin' t' get it t' work consistently. Arrr! Avast, me proud beauty! T' two readings I got from it were just as bad as t' ones from the first unit, and this capsule was lost in only moderately tall grass on the third flight. Avast, me proud beauty! Two o' us saw right where it came down, ya bilge rat, but we gave up after thirty minutes o' searching. Ahoy! T' bird itself survived its repeated flights without damage.

This is how I think MaxTrax works. Avast! Well, me bucko, blow me down! T' ejection sense switch starts an internal timer, which is stopped by t' shock switch when t' unit hits the ground. Arrr! T' assumed descent rate is then multiplied by t' elapsed time to determine t' altitude. If t' shock switch is activated prior t' touchdown (the capsule does tumble pretty badly, me bucko, t' streamers did nay keep either o' my units pointed straight down), matey, ya bilge rat, t' altitude will be low. Begad! If t' shock switch isn't activated at touchdown (as it will nay be when tied t' a parachute), no altitude will be displayed. Well, blow me down! If t' capsule does nay fall at t' assumed descent rate, me bucko, t' altitude will be erroneous. Begad! Avast! While t' idea behind t' MaxTrax is ingenious, it just doesn't work in practice, at least nay t' way Estes has implemented it.

Recovery:
T' bird is over stable and does have a tendency t' weathercock. Begad! Ya scallywag! At 2.5 ounces in stock trim, me hearties, t' B6-4 is late, shiver me timbers, but t' C6-5 is nearly perfect. These are the only two Estes motors you can fly in t' stock bird, though, arrr, limitin' the altimeter t' two general altitudes, somewhat boring. If it worked, that is; the values I got from me two units just aren't believable. Ya scallywag! I'd rate t' flight characteristics o' t' MaxTrax a one on t' Essence scale, arrr, me hearties, needs a lot of improvement.

Flight Rating: 1 out o' 5

Summary:
When I initially saw MaxTrax, shiver me timbers, I imagined all t' kids that would be usin' it for their school science projects. Once I got some experience with t' thing, I realized that thar were goin' t' be a whole lot tearful young scientists and frustrated Dads this year. Blimey! Twenty-one flights on an RTF has got t' be some kind of record, but I'm afraid that me MaxTrax's durability was due t' me preemptive mods. Ahoy! Given t' overall quality o' t' bird, poor altimeter design, me hearties, limited flight scope and ensuin' high possibility o' disappointment, me hearties, I'd rate the MaxTrax a 1½ overall on t' Essence scale, needs drastic improvement.

Overall Rating: 1 out o' 5