AeroTech J435WS-13A DMS vs Reload: 38mm Motor Choice

Quick answer

Choose the AeroTech J435WS-13A DMS kit when you want a 38mm motor with no reusable hardware to clean or track; choose a 38mm RMS reload when you already own the case and plan to fly that case size repeatedly. The DMS kit still requires you to set the delay with a Universal Delay Drilling Tool and add the ejection charge before flight.

What the J435WS-13A DMS kit actually requires

The AeroTech Disposable Motor System (DMS) is a single-use motor in kit form that you assemble yourself. The nozzle and propellant come pre-installed, so your work is limited to setting the delay and pouring the ejection charge. That sounds close to ready-to-fly, but the delay step is not optional: you must use the Universal Delay Drilling Tool (UDDT), which is not included, to set the desired delay time before adding the charge.

For a 38mm airframe, the practical trade-off is that the DMS kit removes case cleaning and hardware inventory but adds a one-time tool purchase and a delay-drilling step at the field. If you do not already own a UDDT, factor that into the cost of your first DMS flight.

Where 38mm reloads (RMS) fit differently

A 38mm reload kit assumes you own the matching RMS motor hardware. In exchange, you buy reload kits rather than complete motors, and you clean and reassemble the case between flights. The J435WS-13A DMS kit avoids that hardware cycle entirely because all components are disposable.

The comparison is not about which motor is more powerful—both are 38mm-class options—but about your launch workflow. DMS suits occasional flyers or projects where cleaning a case is impractical; RMS suits regular flyers who already carry the hardware and want to reuse it across many flights.

Delay setting is the shared bottleneck

Both paths require you to match the delay to your rocket and flight profile. With the J435WS-13A DMS kit, the delay is set by drilling the pre-installed delay element with the UDDT and then adding the ejection charge. With a reload, delay adjustment depends on the specific reload kit and its supplied delay components.

If you fly with a club that has a UDDT on the field, the DMS delay step is quick. If you fly independently, budget for the tool and practice the drilling procedure on a spent or spare delay element before your first live flight.

Trade-offs at a glance

• Hardware and cleanup: DMS: all-disposable components, no case to clean or store. RMS: reusable case must be cleaned and reassembled after each flight. If you dislike post-flight cleaning, DMS removes that task.
• Delay setup tooling: DMS: requires the Universal Delay Drilling Tool (UDDT), not included, to set the delay before adding the ejection charge. RMS: delay adjustment depends on the reload kit's supplied components. Check whether you or your club already own a UDDT before committing to DMS.
• Cost pattern over time: DMS: each flight uses a complete disposable motor kit. RMS: initial hardware purchase plus reload kits per flight. Fly rarely or in small batches: DMS avoids hardware cost. Fly often on the same case: RMS spreads hardware cost across many flights.

Product facts

• AeroTech J435WS-13A 38mm x 356mm Single Use DMS 1-Motor Kit - 104314: The AeroTech J435WS-13A 38mm DMS kit is a single-use motor assembled by the user, with nozzle and propellant already installed. You skip case cleaning and hardware tracking, but you still must complete the delay and ejection-charge steps before flight.

  

Which should you choose?

Choose the J435WS-13A DMS kit if

• You want a 38mm flight without owning or cleaning RMS hardware.
• You have access to a Universal Delay Drilling Tool and are comfortable setting the delay and ejection charge yourself.

Choose a 38mm RMS reload instead if

• You already own the matching 38mm RMS case and fly it regularly.
• You prefer to avoid disposable motor kits and want a reusable hardware system.