CIVIL PROTECTION AND SAFE SKY

Transcription

1 CIVIL PROTECTION AND SAFE SKY DURING THE SPACE VEHICLES REENTRY DeCAS PATENTED An alert system for the safety of people and things on the Earth s surface and for the safety of aircraft and space vehicles in flight 26 November 2015 Prof. Piermarco F. Martegani Info@aviosonic.it

2 When danger comes from the sky In the Earth s orbit, there are about 13,000 objects. For most of them, the disposal will be through the re-entry into the atmosphere as required by international agreements between agencies in different countries. (i.e NASA Safety Standard Process for Limiting Orbital Debris) With the new satellite technologies and the advent of space tourism SV reentries in the atmosphere are expected to rise considerably over the next few years. Today we are forced to close airspace supposedly concerned with these reentries (with strong economic impact) and to live moments of uncertainty and apprehension

3 When danger comes from the sky The fragmentation of a space vehicle (satellite or spacecraft) during reentry to the Earth can be planned or accidental, as in the case of Columbia. The debris that is generated, whose position is always uncertain, can be very dangerous to the population and to high-risk industrial plants (i.e. nuclear power plants) in addition to the civil and military aviation. GOCE reenters atmosphere Knowing the location and extent of the debris (or danger area), as well as its dynamics, allows us to secure and notify all potentially interested parties in time. Meteor over Chelyabinsk (Equivalent to a possible Satellite reentry effects over a town)

4 Space systems in LEO reenter naturally at very small angle (<1 degree). Location of uncontrolled reentries is unpredictable Major breakup at ~78 km 10 to 40% of mass survives reentry and impacts the Earth s surface posing hazard to people and property (e.g. of the ATV-1 mass of 12.3 tons about 3.5 tons in 183 fragments survived reentry, 28.4% of mass) Debris spread over long, thin ground footprint (e.g. for ATV ~ 817km by 30km) Space Debris Problem Brazil, 2012 South Africa, 2000 New Mexico 2014 Saudi Arabia, 2001 Mongolia, 2010

5 Space Debris Impact Prediction Generally assume ±10-25% error in time of reentry due to atmospheric and drag uncertainties Example: Prediction made with tracking data 1 orbit revolution (90 minutes) from reentry has ±9 minute error Object travelling at 7.5 km/sec x ±9 minutes ±4050 km uncertainty in reentry location Some official sources of reentry predictions for uncontrolled reentry send messages released at intervals (T-4 days, T-3 days, T-2 days, T-1 day, T- 12 hrs, T-6 hrs,t-2hours)

6 WHERE? Impact point for surviving fragments is also impossible to predict Spread of fragments will depend on where fragments are released and flight characteristics of each fragment Fragments impact many kilometers from each other Local wind can be a significant factor Uncertainties are addressed by footprint probability boxes (e.g. 1x10-5, and 1x10-2) Footprint probability boxes are routinely used to determine re-entry maneuvers for controlled re-entries (e.g. ATV)

7 Range Commanders Council defines the Aircraft Vulnerability Models (AVMs) to quantify the areas of aircraft susceptible to catastrophic event. RISK FOR AVIATION Aircraft modeling Impact consequences analysis Fragment< 300gr Tanks Cockpit Engines A fragment more than 300gr causes loss of aircraft.

8 A NEED FOR AEROSPACE SAFETY A system able to: determine the exact condition of explosion / fragmentation of Space Vehicle early warn the users potentially affected transmit the dynamics of Danger Area to all interested users provide the elements to suggest" to pilots a initial escape heading to avoid danger area

9 DeCAS - Debris Collision Alerting System (PATENTED) The system which is small in size and lightweight, is based on the principle of the black box of the aircraft and it uses space technologies already tested for data broadcasting It is fitted into or on the vehicle during the construction phase remaining in a dormant status until it activates by itself at the moment of fragmentation of spacecraft sending information about its location (which corresponds to the space debris area) It is useful both in the launch phase (detachment and re-entry of the various stages of combustion) and in the re-entry phase. Not in scale

10 DeCAS Integration (PATENTED) Hence DeCAS works as a smart fragment which can autonomously determine its own position during re-entry and which knows its relative location in the projected hazard area which has been pre-computed on ground and/or its data are used directly from a ground station to determine the Dangerous Area

11 Use of DeCAS and reference market Alerting people of the potential danger Market: The Civil Protection Centers around the world Sites of the population potentially affected by the falling of the fragments Allowing the safety of sensitive installations Market: Atomic, Chemical and Electrical power plants, oil and gas platforms, dams, space and military sites, production and special sites etc Avoid the imminent collision of aircraft with space debris Market: All the civil and military aviation (Airlines, Air Traffic Control Centers, general aviation etc) Coverage of the areas where the ATC service is not available Market: air traffic on intercontinental routes and areas not covered by the air traffic services, large sea vessels on intercontinental routes. As a supplementary system to the future contingency procedures for international flights (long-haul flights) during the launch and reentry of Space Vehicles

12 THANK YOU