Oman York Conference(2001 in press)11/2/01 2.5 3D spatial memory and navigation difficulties. The US and Russian space program gradually evolved to using larger vehicles with more complex three dimensional architectures For practical reasons, the local visual verticals in different modules are not universally coaligned Ground trainer modules are not al ways physically connected in the same way as they are in the actual vehicle. Therefore, occupants say that they have difficulty visualizing the spatial relationships between landmarks on the interiors of the two modules. They cannot point in the direction of familiar interior landmarks in other modules the way they say they could when in their homes on Earth. They often do not instinctively know which way to turn when moving between modules through symmetrical multi-ported nodes. Shuttle crew visiting the Mir station (Figure 4)often had difficulty finding their way back, without assistance from Mir crewmembers, or arrows fashioned and positioned to help them( richards, et al, 2001) Comparable problems have not been described within the US Shuttle itself, probably because the flight deck, mid-deck, and payload bay research modules have coaligned and less ambiguous internal visual verticals. Maintaining spatial orientation during EVA activity on the outside of the Mir and International Space Station was sometimes also difficult, particularly during the dark half of each orbit, due to the lack of easily recognizable visual landmarks Several operational crises which occurred in 1997 aboard the Russian mir station convinced crewmembers and human factors specialists that the ability to make three dimensional spatial judgements is important in emergency situations and critical if an emergency evacuation Is necessary in darkness or when smoke obscures the cabin Twice when collisions with Progress spacecraft were imminent, crewmembers moved from module to module and window to window, unsuccessfully trying to locate the inbound spacecraft. Another emergency required the crew to reorient the entire station using thrusters on a docked Soyuz spacecraft Members of the crew in the mir base block module discovered they had great difficulty mentally visualizing the orientation of another crewmember in the differently oriented Soyuz cockpit, and verbally rel the appropriate commands( Burrough, 1998) 4. Russian mi e station had four research modules connected to a central node Related difficulties are being encountered on Visual verticals of some modules were not the new International Space Station. Egress routes to Shuttle and Soyuz require turns in potentially disorienting nodes. Emergency gress Is comp of rescue vehicles, so different crewmembers are assigned different vehicles and egress routes One early station crew placed emergency Exit signs beside the node hatches, but subsequentlyOman York Conference (2001 in press) 11/2/01 Page 6 2.5 3D spatial memory and navigation difficulties. The US and Russian space program gradually evolved to using larger vehicles with more complex three dimensional architectures. For practical reasons, the local visual verticals in different modules are not universally coaligned. Ground trainer modules are not always physically connected in the same way as they are in the actual vehicle. Therefore, occupants say that they have difficulty visualizing the spatial relationships between landmarks on the interiors of the two modules. They cannot point in the direction of familiar interior landmarks in other modules the way they say they could when in their homes on Earth. They often do not instinctively know which way to turn when moving between modules through symmetrical multi-ported nodes. Shuttle crew visiting the Mir station (Figure 4) often had difficulty finding their way back, without assistance from Mir crewmembers, or arrows fashioned and positioned to help them (Richards, et al, 2001) Comparable problems have not been described within the US Shuttle itself, probably because the flight deck, mid-deck, and payload bay research modules have coaligned and less ambiguous internal visual verticals. Maintaining spatial orientation during EVA activity on the outside of the Mir and International Space Station was sometimes also difficult, particularly during the dark half of each orbit, due to the lack of easily recognizable visual landmarks. Figure 4. Russian Mir space station had four research modules connected to a central node. Visual verticals of some modules were not coaligned. Several operational crises which occurred in 1997 aboard the Russian MIR station convinced crewmembers and human factors specialists that the ability to make three dimensional spatial judgements is important in emergency situations and critical if an emergency evacuation is necessary in darkness, or when smoke obscures the cabin. Twice when collisions with Progress spacecraft were imminent, crewmembers moved from module to module and window to window, unsuccessfully trying to locate the inbound spacecraft. Another emergency required the crew to reorient the entire station using thrusters on a docked Soyuz spacecraft. Members of the crew in the MIR base block module discovered they had great difficulty mentally visualizing the orientation of another crewmember in the differently oriented Soyuz cockpit, and verbally relaying the appropriate commands (Burrough, 1998). Related difficulties are being encountered on the new International Space Station. Egress routes to Shuttle and Soyuz require turns in potentially disorienting nodes. Emergency egress is complicated by the limited capacity of rescue vehicles, so different crewmembers are assigned different vehicles and egress routes. One early station crew placed emergency “Exit” signs beside the node hatches, but subsequently