Upgrade of LATSA
Page 49 of 148
charts in ASHRAE 872-RP: Psychrometrics – Theory and Practice ASHRAE, 1996, and sample
calculations provided in Stull 2000.
4.6.1 Aircraft operational constraints
In utilising version 2.0 of LATSA, the Participant Exporter assumes that the nominated aircraft can operate at its full design ECS capacity. Where the Participant becomes aware that the
aircraft has temporary ESC limitations and checks that box in the document section of the program, progress is halted until that issue has been discussed and managed with the carrier.
Version 2.0 of LASTA also assumes that each aircraft is operating to its respective maximum or minimum design specification. As an example, the inlet air temperature for a Boeing 747-400 is
specified as 2
C and that inlet temperature is used by the program as the inlet temperature constant for that aircraft.
Selection of the correct aircraft is therefore an important factor when utilising version 2.0 of LATSA.
4.7 Software Development
The validation process incorporated the development of a Microsoft Excel© spreadsheet which calculated results for single species configurations. This spreadsheet utilised the equations and
methodology developed throughout the research phase of the project and results from the spreadsheet were utilised in the validation phase.
The database tables extracted from LATSA V1.0, the spreadsheet, completed reports, an equation list and the calculation methodology were used in the development of the SQL
database and web based interface. The structure and specification of the software has been discussed in Section 3.3. The
incorporation of numerous issues in regard to aircraft, operators, holds, crates and animals generated significant complication due to the number of possible combinations. The table
structure includes multiple linkages and many of the resulting selections are not unrestricted. While some fields e.g. Embarkation Ports and Operator’s Aircraft have been specifically
restricted, the provision of additional selection limitations was seen as both detrimental to acceptance of the system and more difficult to administer in the initial stages of release.
The development process involved several iterations of presentation, test, challenge and modification prior to its initial release to MLA and LiveCorp representatives. At least two more
iterations occurred before presenting the program to potential users to test. Users were encouraged to enter actual data in order to identify any missing selections and inappropriate
outcomes. The methodology relating to animal physiology remained consistent throughout the software
development phase. However some modifications were made to the methodology relating to aircraft ventilation as the software development proceeded in order to model results equivalent to
actual outcomes.
It was assumed that recirculation systems effectively mix air within a hold; Recirculated air was excluded from air mixing calculations. Only ventilation exit air flow
was incorporated;
Upgrade of LATSA
Page 50 of 148
The volume ratio for non livestock cargo remains defined and constant; The inlet air temperature was defined as the lowest design temperature for the aircraft;
The inlet air humidity was set to 10 RH; The effect of animal disturbance in-flight was limited to a 10 increase in physiological
outputs; Much of the early effort in software development was concentrated on scientific and engineering
outcomes. While this was necessary to ensure calculated outcomes accurately reflected the actual physical response, it became apparent that presentation rather than calculation
methodology was the most critical factor for industry acceptance. Several of the latter iterations of test and modification resulted in relatively minor changes to data presentation.
Information relating to the operation of the system have been separated into Administration and User Manuals. Compete versions of these manuals can be found in Section 9.8 Appendix 8 –
LATSA V2.0 Administrators Manual and Section 9.9 Appendix 9 – LATSA V2.0 Users Manual
4.8 Use of equations within version 2.0 of LATSA
