Third accident in three years: Hermes 900 becomes a crash drone

An Elbit drone has crashed in the Philippines. In Israel, the manufacturer received the world’s only permission to fly in civil airspace, despite similar incidents. Soon Switzerland will follow.

An unmanned aerial vehicle of the type Hermes 900 suffered total damage in an accident in the Philippines on Saturday. The crash landing occurred on approach to Lumbia Airport on Mindanao Island, apparently after communications with the drone were interrupted. It was reportedly on a test flight to test various functions.

No people or buildings are reported to have been harmed in the crash in forested terrain. The drone is now being recovered. The Philippine Air Force is investigating the cause of the incident. For the time being, all drones of the same type must remain on the ground.

Drone is considered combat-proven

According to reports, the Manila government has ordered nine Hermes 900s from Israeli manufacturer Elbit, spending about $175 million. They can be used for surveillance or search and rescue missions. Last year, Elbit unveiled a maritime version that can drop life rafts; its deployment is to be by an unnamed customer in Southeast Asia.

The Hermes 900 has a wingspan of 15 metres and a maximum take-off weight of 1,180 kg. With a flight altitude of up to 10,000 metres and an endurance of up to 36 hours, it belongs to the Medium Altitude Long Endurance (MALE) class of drones.

In Israel, the Hermes 900 is considered combat-proven, but it is only exported unarmed. Like its predecessor, the Hermes 450, it is one of the most frequently used military drones in the world. Deliveries have been made to Chile, Colombia, Brazil, Mexico, Azerbaijan and Singapore. Most recently, the military in Uganda reportedly ordered two dozen Hermes 900s.

Accident in Frontex operation

Three years ago, the border agency Frontex also used a Hermes 900 for border surveillance. The drone was stationed on Crete for this purpose, and the flights were carried out under the responsibility of the EU Maritime Safety Agency (EMSA). At the beginning of January 2019, the aircraft crashed on the runway of Tympaki airport during landing.

According to the EU Commission, it was not a crash but a „hard landing“ after sensors on the drone had previously indicated „unexpected readings“. Thus, the fuselage, wings and sensors were damaged, but there were „no casualties nor damage on the running way“.

Previously, a Hermes 900 flew off Iceland on behalf of EMSA, missions were carried out for the coast guard there. It was the first deployment of the Israeli drone under difficult wind and weather conditions over several months.

Competitor crashes too

Since the crash on Crete, EU agencies have not used Hermes 900s. Two years ago, Frontex awarded a contract for long-range drone flights in the Mediterranean, and Elbit’s competitor Israel Aerospace Industries won with its Heron 1.

However, the Heron 1 is also a model that flies anything but accident-free. The German Armed Forces used the drone in Afghanistan from 2010, where it was launched and landed by Airbus technicians. The defence company was selected by the Bundeswehr procurement office as the prime contractor for the framework contract.

At least four of the aircraft deployed in Afghanistan had accidents either on the tarmac or in flight and had to be replaced by the manufacturer. In at least one case on the runway, Airbus pilots are said to have been responsible for this, in another case the drone collided „with a mountain“.

First „roll tests“ in Switzerland

The army in Switzerland is also one of Elbit’s unfortunate customers. It was only at the end of April this year that the delivery of two drones, including the necessary ground stations and logistics, was made, which had been delayed for years. The programme, which cost around 300 million Swiss francs, had been delayed after a Hermes 900 destined for Switzerland crashed and was totalled during a test flight in Israel in August 2020.

The accident report says the airbrakes generated vibrations that pushed the aircraft to the flutter limit at high speeds. This caused the drone’s distinctive V-tail to break off. Elbit subsequently changed the configuration of the flaps and demonstrated airworthiness in „flutter test flights“.

In Switzerland, the Hermes 900 operate under the name of Reconnaissance Drone System 15 (ADS 15) and are intended to modernise the predecessor programme ADS 95 with several Hermes 450. Currently, the first „roll tests“ are taking place on a military airfield. These are intended to verify proper contact with the ground control station. The first flight is scheduled for June, and four more Hermes 900s will be delivered by the end of 2023.

Flights in civil airspace

Despite at least three serious accidents in three years, the Israeli Civil Aviation Authority has issued a permanent permit for Hermes 900 flights in civil airspace there. This is believed to be the world’s first type certificate for an unmanned aircraft of this size. According to a spokesperson, Elbit worked on it for six years.

The drones used by the military are now – for training, for example –  coordinated by civilian air traffic controllers. For this, they carry a sense-and-avoid system on board. According to the Israeli Aviation Authority, its certification meets the applicable NATO standards for the integration of heavyweight drones.

From the end of 2024, Switzerland also plans to allow its Hermes 900 to fly in civil airspace. Before that, however, the sense-and-avoid system still needs to be approved by the Swiss aviation authority. Subsequently, the drone will also be used by police and emergency services as well as border guards.

Image: The Hermes 900 in the Swiss military (Swiss Army).

Autor: Matthias Monroy

Knowledge worker, activist, editor of the German civil rights journal Bürgerrechte & Polizei/CILIP.