In a hangar in southern Chile, while radars keep tracking supersonic fighters and next-generation drones, a veteran aircraft is living its own silent revolution. The DHC-6 Twin Otter, that compact Canadian aluminum workhorse, keeps taking off with the same grit as always, but now with something new under its fuselage: technology, autonomy, and strategic purpose.
For more than four decades it has been one of the main workhorses of the Chilean Air Force’s transport aviation. Since its arrival, the Twin Otter became an irreplaceable operator in territories where there is nothing: no runways, no towers, no spare parts within reach. From Puerto Montt to Antarctica, these aircraft have done everything that can be asked of an airplane: carry cargo, evacuate patients, mark presence, map the void, and train the transport pilots who complete their multi-engine course in Aviation Group No. 5. In terrain where the weather can close in five minutes, its reliability turned it into a legend. And like every legend worth its name, instead of being retired, it transforms.
The decision is not trivial. Replacing a fleet like this not only costs millions. It means losing a proven, adapted, and familiar platform. Instead, ENAER — the National Aeronautics Company of Chile — opted for a more complex but smarter formula: transforming what already exists. And it is doing so with a mix of precision engineering, creativity, and accumulated knowledge.
The change is profound. The old analog gauges were replaced by digital screens. The new avionics meet standards for operating where navigation aids are scarce and the weather is complex. But it is not just about adding screens: the work touched everything. Front compartments were installed to increase cargo capacity, the engines were repowered, the oxygen system was reinforced for long flights at high altitude, and the fuselage was reconfigured to convert Series 100 models into the robust and versatile Series 300.
One of the most ambitious modifications: turning it into an aerial exploration platform. A state-of-the-art aerial photogrammetry camera was installed, but it was not just a technical upgrade. Its structure had to be surgically modified: automated hatches opened, dedicated GPS antennas installed, anti-fogging systems developed. In other words, adapting a 20th-century aircraft for 21st-century scientific tasks. Because this is not just a technical improvement. It is a geopolitical move.
On a chessboard where Chile’s projection over Antarctica must be sustained with deeds rather than words, having an operational and upgraded fleet of Twin Otters becomes a tool of sovereignty. While the white continent turns into a stage of scientific competition and international presence, Chile strengthens its logistical capability with an aircraft that does not need major airports, that can operate on improvised runways, and that now, thanks to its new avionics and greater autonomy, can go farther with less.
This transformation is a sovereignty strategy. With extended autonomy, modernized avionics, greater cargo capacity, and aerial reconnaissance tools, the upgraded Twin Otters consolidate routes, support Antarctic science, and keep remote areas of the country connected. All with an aircraft cheaper to operate than a large transport, highly reliable, and capable of operating on short, improvised runways, adaptable to scientific exploration, rescue, and logistical transport.
It is, ultimately, a demonstration that a well-maintained and upgraded veteran is as strategic as an entirely new system.
What is relevant is that, through ENAER, much of the technical muscle today is in Chile. The design of auxiliary fuel tanks that extend range by three hours is just one example of the kind of tailor-made solutions the national industry is developing. What used to be a dependence on foreign manuals is today an installed capability: parts are designed, wings reinforced, cockpits adapted, painted, and certified.
But like every good story of resilience, there is a limit. The Twin Otter is not immortal. No matter how modern its cockpit or more reliable its engines, the fuselage has decades of history behind it. Keeping them flying is a battle against obsolescence and corrosion. The dilemma is not resolved: how long can the useful life of a veteran aircraft be stretched without compromising safety or efficiency? Sooner or later, the debate over a structural replacement will arrive. But for now, as long as that moment is not inevitable, the aircraft keeps fulfilling its mission.
In times when defense is measured in millions and missiles, the Twin Otter reminds us of the essential: sovereignty is also built with constancy. With routine flights in Antarctica, with permanent presence in extreme zones, and with decisions that prioritize adaptability over grandiloquence.
Thus, without making noise, without hitting headlines, the Twin Otter remains one of the most strategic assets of Chilean air transport.
And in a long, seismic, polar, and remote country, that is no small thing.
ENAER and its logistical support: keys to modernization
- Auxiliary fuel tanks
Since 2018, ENAER designed and manufactured three tanks that add almost 3 hours of autonomy to the Twin Otter. And it is not theory: those tanks were key in Operation Polar Star III, when two Twin Otters reached the South Pole from Union Glacier in January 2025. - Improved power
Between early and late 2024, three aircraft were received for repowering: their Pratt & Whitney PT6-20 engines were upgraded to the PT6-26 series, improving performance and reliability. At the same time, structural maintenance, anti-corrosion treatment, and painting were applied. - Conversion from Series 100 to Series 300
This process integrates several key improvements: long nose for more cargo, reinforced oxygen system, modification of control surfaces, vortex generators, stall strips, and PT6A-27 engines with compatible propellers. Two aircraft have already been converted, one is in process, and the fourth will arrive in 2026. - “Glass Cockpit” digital cabin
ENAER replaced analog instruments with digital multifunction displays in some Twin Otters, aligning them with current navigation and safety standards. - Aerial mapping platform
In Punta Arenas, a Vexcel Ultracam Eagle Mark 3 camera was installed. To this end, a structural support, a dedicated GPS antenna, lens protection, and anti-fogging system were designed. The test flight was on August 4, 2025. - Comprehensive support
ENAER does not just upgrade isolated parts. It offers overhaul, structural repairs, part manufacturing, anti-corrosion treatments, interiors, painting. A complete package to keep Twin Otters flying in extreme conditions.
Photographs used for illustrative purposes – Chilean Joint Chiefs of Staff and Chilean Air Force (FACh).
*Original text written in Spanish by Rodolfo Neira Gachelin
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