Why the plug matters as much as the headset
A headset's noise reduction, comfort and Bluetooth capability are irrelevant if it does not physically connect to the aircraft it is being flown in. The connector standard is a separate specification from everything else about a headset, and mismatching it is the most common, and most avoidable, mistake in a headset purchase.
Dual GA: the general aviation standard
The dual GA plug pairs two separate connectors: a quarter-inch PJ-055 plug carrying headphone audio, and a smaller 0.206-inch PJ-068 plug carrying the microphone signal. This is the connector fitted to the overwhelming majority of fixed-wing general aviation aircraft, and it is the configuration a first-time headset buyer should expect unless told otherwise. The David Clark H10-13.4 uses dual GA plugs as standard, and the Lightspeed Zulu 4 offers dual GA as one of its available plug options.
U-174: the helicopter connector
Rotary-wing aircraft, and a range of military fixed-wing types, generally use the U-174/U connector instead, sometimes referred to as the NATO or helicopter plug. It is a single, more rugged multi-pin connector carrying both headphone and microphone signals through one plug rather than two, reflecting the more demanding vibration and handling environment of a helicopter cockpit. The Zulu 4 lists U-174 among its available plug options, which is the point worth remembering: the same headset model is frequently available in more than one plug configuration, and ordering the wrong one is a configuration mistake, not a hardware limitation of the headset itself.
LEMO 6-pin: panel-powered ANR
Where an aircraft's panel provides power to the headset jacks directly, ANR headsets can skip batteries entirely and draw power through a single round LEMO 6-pin connector instead. This removes battery management from the pilot's checklist altogether, at the cost of only working in aircraft actually wired to supply panel power in the first place. The Zulu 4 lists panel-power 6-pin as one of its plug options alongside dual GA and U-174, illustrating how a single ANR headset design is offered across all three connector standards depending on what the buyer's aircraft actually provides.
What this means when ordering
- Identify your aircraft's headset jack configuration before ordering, not after the headset arrives. Most fixed-wing GA aircraft take dual GA; most helicopters take U-174; some newer GA aircraft and business jets wire panel power through LEMO.
- If you fly more than one aircraft type, plan for it explicitly: some pilots keep one headset with the plug matching their primary aircraft and use an adapter for occasional flying in a different type, rather than buying two full headsets.
- Panel power (LEMO) is worth asking about specifically if your aircraft supports it, since it removes battery anxiety from an ANR headset entirely, but confirm the aircraft is actually wired for it before ordering a LEMO-configured headset.
- Airliner and Airbus-type XLR-5 connectors exist as a fourth standard in commercial transport aircraft, outside the general aviation and helicopter fleet most buyers of the headsets covered here will be flying.
Getting it right the first time
ASPL supplies the Bose A30, Lightspeed Zulu 3 and Zulu 4, and the David Clark H10-13.4, and can confirm the correct plug configuration for your specific aircraft before you order, which is a five-minute conversation that avoids a returned headset and a delayed flight.