Yes, some newer Twin Otter aircraft do have a wire running from the top of the cockpit to the top of the tail, as do some legacy Twin Otter aircraft. That wire is a high-frequency (HF) antenna, which allows the flight crew to use an HF radio.
HF radios are an optional feature of both legacy and newer Twin Otters. HF radio is often used in areas lacking infrastructure, as it is a reliable form of remote communications with long range and interoperability capability. This makes them ideal for the remote areas where the Twin Otter excels. Not all Twin Otter operators require the redundancy and long-range format that HF radio provides, which is why it’s optional and not standard equipment.
The Series 400 Twin Otter has a number of additional configurations and options, allowing you to customize your aircraft to fit your needs. Tell us your mission and we’ll give you a customized analysis of what options are best suited for you.