ExoMars - High Altitude Drop Test (HADT)
The ExoMars HADT is a program developed by ARCA for the European Space Agency (ESA), that aims to test the ExoMars spacecraft parachutes. The ExoMars spacecraft will be launched in 2016.
The ExoMars spacecraft consists of a space probe named ESA Orbiter and a Mars landing module, named ESA EDL Demonstrator Module. ARCA's role in the ExoMars program is to test the atmospheric deceleration parachutes of the EDL module in conditions similar to the ones in the Martian atmosphere. The parameters to be analysed will be parachute deployment loads, parachute stability, the drag coefficient and the overall system stability.
System overview
In order to successfully test and qualify the EDL demonstrator module parachutes, ARCA will carry out two stratospheric flights, named High Altitude Drop Test (HADT) and one avionics qualification flight. ARCA have built the two DTV (Drop Test Vehicle). The two built DTVs are aerodynamically stable and are equipped with the parachute deployment system and the avionics supplied by ESA. Furthermore ARCA will contribute with its own avionics and data transmission complementary systems. ARCA also constructed the balloon gondolas that are placed between the DTV vehicle and the helium balloon. The gondolas are equipped with avionics and data transmission systems provided by ARCA.
Hardware description
Balloon
The balloon has a volume of 1,700,000 cubic feet (50,000 cubic meters) and is filled with helium.
Gondola
The balloon gondola is a cylindrical pressurised capsule that was constructed from composite materials. Inside the gondola were placed radio and satellite avionics systems that are tracking the balloon and two HD cameras that will capture the vehicle detachment moment and the subsequently balloon burst.
DTV
The Drop Test Vehicle (DTV) is an aerodynamic structure with four stabilisers at the rear end. It is also built from composite materials and is designed to fly at transonic speeds, to support the parachute deployment loads and the acceleration on water landing. The DTV is equipped with a separation system from the balloon, avionics systems, the parachute system, and the parachute test instruments. The vehicle maximum diameter is 2.8 ft (0.85 m) without the stabilisers, 8.4 ft (2.55 m) with stabilisers and the overall length is 6m (including the Pitot). The stabilisers are built from 2024 T6 aluminium alloy. The separation system is composed of three pneumatic pistons supplied from a 200 bar pressure canister.
The parachute deployment system consists of the explosive triggering component, the 39 ft (12 m) diameter parachute, the parachute container, the BoP drogue and the interface ring with the DTV airframe.
DTV technical data
Length (m):
Diameter (m):
Wing span (m):
Launch mass (kg):
Launch altitude (m):
Max. speed (Mach):
Parachute opening load (kgf):
Max. autonomy (hours):
6
0.85
2.55
604
29,000
0.8
9,700
8
HADT, avionics qualification flight
ARCA has successfully completed the avionics qualification test flight for the ExoMars High Altitude Drop Test (HADT).
The objectives were flight testing the avionics and communication systems, demonstrating the container sealing after sea landing and the capability to identify and recover the equipment from the sea surface.
The launch took place on September 16, 2013, from the Black Sea coast and comprised three pressurised containers containing the avionics equipment that will be necessary to test the ExoMars spacecraft parachute during the incoming future flights.
The pressurised containers, carried by the cluster balloon, were launched at 7:15 AM and the ascension took 90 minutes to an altitude of 24,470 km. At this altitude the containers were released under a dedicated recovery parachute and landed on the sea, twenty minutes later. The containers and the recovery parachute were recovered by the Navy, at a distance of 92 km from the launch point.
