The Major Constituent Analyzer (MCA) is a mass spectrometer-based atmospheric monitoring instrument in the Laboratory Module of the International Space Station (ISS). The MCA is used for continuous environmental monitoring of 6 major gas constituents in the ISS atmosphere as well as safety-critical monitoring for special Environmental Control and Life Support (ECLS) operations such as Pre-Breathe in the Airlock for Extra-Vehicular Activities (EVAs) and oxygen re-pressurizations. For the latter, it is desirable to make most efficient use of consumables by transferring the maximum amount from O2 re-supply tanks on board the shuttle or Progress. The upper safety limit for O2 transfer is constrained by the MCA measurement error bands. A study was undertaken to tighten these error bands and afford NASA-Mission Operations Directorate (MOD) more operational flexibility.The MCA has a fully self-contained calibration capability and on-orbit experience indicated the stability and precision of MCA atmospheric measurements were well within specified limits, so a more rigorous study was undertaken to quantify sources of error. This study examines on-orbit and terrestrial data and performs statistical and error analyses for various operational modes and environmental conditions. The results are compiled into a database that projects MCA partial pressure constituent accuracies under various operational modes and conditions (such as time since last self-calibration).This study concludes that a significant margin exists between demonstrated and specified MCA accuracy. Forward work includes an assessment of the process necessary to re-certify the MCA to a tighter error tolerance band and thus provide MASA-MOD with increased operational flexibility.


    Zugriff

    Zugriff prüfen

    Verfügbarkeit in meiner Bibliothek prüfen

    Bestellung bei Subito €


    Exportieren, teilen und zitieren



    Titel :

    Accuracy Assessment of the Major Constituent Analyzer


    Weitere Titelangaben:

    Sae Technical Papers


    Beteiligte:
    Steiner, George (Autor:in) / Granaham, John (Autor:in) / McHard, Richard (Autor:in) / Reysa, Richard (Autor:in)

    Kongress:

    International Conference On Environmental Systems ; 2005



    Erscheinungsdatum :

    11.07.2005




    Medientyp :

    Aufsatz (Konferenz)


    Format :

    Print


    Sprache :

    Englisch




    Accuracy Assessment of the Major Constituent Analyzer

    Steiner, G. / McHard, R. / Reysa, R. et al. | British Library Conference Proceedings | 2005


    Improving the Measurement Accuracy of Water Partial Pressure Using the Major Constituent Analyzer

    Tissandier, Amber M. / Gardner, Ben D. / Erwin, Phillip M. et al. | SAE Technical Papers | 2009


    Hardware Design Improvements to the Major Constituent Analyzer

    Gardner, Ben / Combs, Scott / Thoresen, Souzan et al. | AIAA | 2011


    On-Orbit Performance of the Major Constituent Analyzer

    Ransom, Elizabeth / Steiner, George / Gentry, Gregory et al. | SAE Technical Papers | 2002


    International Space Station Major Constituent Analyzer On-orbit Performance

    Gardner, B. / Erwin, P. / Thoresen, S. et al. | British Library Conference Proceedings | 2012