Essay
Excerpt from FliteERJ Performance feasibility study, 2002 Jul 24.

 


1. Contact Address

The responsible author can be reached via

Christoph Regli
Dipl. Inf. Ing. ETH
Werftstrasse 40
CH-8302 Kloten
Switzerland

+411 814 30 25
+4179 310 30 22

info@flite.ch
http://www.flite.ch/

2. Introduction

This document describes the FliteERJ Performance project for the Embraer 145 fleet, an extension of the FliteERJ M&B calculation tool available at http://www.flite.ch/, with T/O and LDG performance databases. Its main goal is to have all performance related data at hand, integrated into and interfacing to the mass and balance calculation environment FliteERJ.

2.1 How to read this Document
Chapter 3 gives an overview of the project and describes its main goals. Chapter 4 outlines the advantages and drawbacks/risks of an implementation and summarizes the financial aspects. Chapter 5 finally concludes with possible next steps.

2.2 Definitions

APP Approach.
Cradle Usually, the HotSync process is done via a cradle, an interface to attach the Palm device to the desktop PC. As there are various Palm handheld models, there are as well different cradles.
EFCOP Engine failure climb-out procedure.
HotSync is the process of synchronizing data between the handheld and the desktop computer. It is of bi-directional nature, i.e. data entered on the Palm handheld is updated on the desktop computer, while the handheld gets the latest data from the desktop PC.
IR Infrared. All newer Palm handheld devices support data transfer via infrared.
LDG Landing.
M&B Mass and balance.
MAA Minimum acceleration altitude.
MLM Maximum LDG mass.
OEI One engine inoperative.
Palm A Palm computing device is a palm sized portable handheld computer based on Palm OS.
RPM The route performance manual containing T/O performance data and EFCOPs.
RTOM Regulated T/O mass.
RWY Runway.
T/O Take-off.

 

2.3 Legal Terms
Palm OS and HotSync are registered trademarks and Palm is trademark of Palm, Inc.

3. Aim Description

3.1 Preface
The FliteERJ mass and balance calculation tool has proven its usefulness in the field in various situations. It acts as a backup of the manual computation of loadsheets while giving a quick hand for determining any ballast or row blocking requirements prior to the calculation of the final loadsheet version, thus giving a time advantage should passenger boarding or the beginning of an ATC slot be impending. Refer to the FliteLX Homepage for more details concerning the FliteERJ loadsheet application.
The next logical step of a Palm handheld assisted flight performance planning is the integration of the route performance manual data. Roughly estimated, the currently used RPM leads to a raw data size of less than 1MB, considering 550 double sided pages (tables 21+6 rows, 4 columns, cell size 6 bytes, plus some 43 bytes of header information and administrative data). - In short terms, the entire content of the RPM easily fits into the memory of a standard Palm handheld model.

3.2 Aimed State
Once available, the RPM database enables interesting and extensive flight performance calculations. The pilot selects the departure runway out of the database and enters some relevant data like actual wind, temperature and QNH. The application then calculates the RTOM based on these values and the RPM database. This RTOM finally appears in the FliteERJ loadsheet application.
Besides that, the program displays the EFCOP and MAA of the selected RWY and lists alternative RWYs should the selected RWY restrict the T/O mass of the actual M&B calculation.
Concerning the LDG performance, the pilot has to select the arrival runway and some influencing factors like contamination, flaps setting and wind, which will lead to a performance limited MLM that can again be transferred into the FliteERJ loadsheet application.
Inflight, the LDG performance calculation may as well be reversed: Given an estimated landing mass and certain conditions, the application calculates the required RWY length under these circumstances.

3.3 A possible Layout
The basic FliteERJ M&B functionality is extended by an import facility of T/O and LDG performance data like the performance limited regulated T/O mass RTOM and maximum LDG mass MLM.

Performance 01.

This is the new register bar of the FliteERJ Performance program. The two buttons with the departing and the landing aircraft icons lead to the T/O and LDG performance related dialogs.

Performance 02.  Performance 03.  Performance 04.

An airport is identified by its three-letter IATA or four-letter ICAO code. All airport identifiers that are covered by the RPM database are displayed in a list. This list will be restricted each time the user enters a further letter of the airport identifier code. - Alternatively, the FliteLX FTDR application may provide the DEP and the DEST airport identifiers.
Once the airport is identified, the application displays a list of all available RWYs that can be selected by a single tap.
Based on that selection and the inputs for the performance calculation, the program looks up the database and interpolates intermediate RTOM values.

Performance 05.  Performance 06.  Performance 07.

The LDG performance page as well lets the pilot select all performance relevant data. Besides the resulting RWY length or MLM, the module calculates the OEI missed APP climb gradient based on the entered values.

3.4 Modules and Interfaces
The diagram shows the layout of the FliteERJ M&B software augmented by the T/O and LDG performance calculation modules. Although the main topic of this document is the FliteERJ Performance application (left part of the diagram), possible links to the FliteLX FTDR program (right side) are as well displayed.

Performance 08.

Legend:

Performance 09.
Printout

 

The printed loadsheet is at the end of the process, providing M&B related information paired with T/O and LDG performance limitations.
The printout is performed by a mobile infrared matrix printer on carbon copy paper. A mobile printer is the preferred solution compared to using the ACARS printer as an interface to any aircraft system requires specific certification by the respective authorities.

 

Performance 10.
FliteERJ Performance

 

This is the FliteERJ M&B calculation software augmented by performance related computation modules.

 

Performance 11.
T/O Perf

 

The T/O performance database is in fact the route performance manual.

 

Performance 11.
M&B

 

The M&B database is the loadsheet algorithm of the FliteERJ application.

 

Performance 11.
LDG Perf

 

The LDG performance database is the factored/unfactored landing distance calculation algorithm according OM-B, section Performance. Note that this part can request the available runway length data from the T/O performance database and get the actual LDG mass in order to display the required RWY length.

 

Performance 10.
FliteLX

 

This is the already released FTDR and flight planning software.
The diagram shows that the FliteLX FTDR application reports the departure, destination and alternate airport identifiers of the next active leg as well as the aircraft immatriculation to the FliteERJ Performance program. These parameters however can as well be selected within the FliteERJ Performance so the program can work autonomously.

 

Performance 11.
Swiss International Air Lines Timetable

 

One database of the FliteLX application is the Swiss International Air Lines timetable, enabling the pilot to enter a flight number in order to retrieve the scheduled departure and destination airport codes.

 

Performance 11.
Operational Airports

 

The airports database integrates, among other information, the standard alternate airports of the operation network airports. Future implementations may incorporate the 10-0 and 10-4 charts of the route manual.

 

Performance 12.
CRX Server

 

As all databases have to be up-to-date in order to assure data integrity, the files stored on the Palm handheld have to be updated in regular intervals. Refer to chapter 'Data Integrity' later on in this document.

 

Load figures The load figures issued by the handling agent like passenger figures, cabin version, baggage, cargo, mail.

 

3.5 Data Integrity
One of the main concerns is the assurance of the integrity of the databases on the Palm handheld. This can be assured by docking stations at each crew base that are linked to the Swiss International Air Lines IT network. Upon check-in, the pilot synchronizes its Palm handheld via infrared connection. The docking station updates any outdated Palm database with the latest version. The advantage of an infrared connection is that the requirement to support all possible Palm cradle layouts for different handheld models becomes obsolete.

4. Evaluation

4.1 Investments
- Palm handheld devices CHF250 each pilot
- IR printers CHF400 each aircraft
- Docking stations and installation CHF2000 each crew base
- Software ...

4.2 Benefits
Manual loadsheets instead of DCS loadsheets
Cost savings per day: η•λ•σ = CHF3000 where
     η = total number of aircrafts (25)
     λ = mean price of a single DCS loadsheet (CHF20)
     σ = mean number of legs per day with DCS loadsheets (6)

Paper based RPM
Given that both pilots possess a Palm handheld device thus redundancy is assured, a paper based RPM and its update service becomes obsolete, saving a considerable amount of costs.

Operational benefits
The pilots can work with an integrated T/O performance, LDG performance and M&B calculation tool. All benefits of the M&B tool that is already in use, paired with the performance part form an handy working environment.

Fallback solution
The manual loadsheet and performance calculation as a backup still exists.

4.3 Drawbacks
My main concern is the acceptance of the crew. The abandonment of DCS loadsheets leads to increased crew workload during turnarounds.
The manual loadsheet as well as the FliteERJ loadsheet algorithm only support class trim. The seat row trim is too time consumptive to being entered manually.

5. Line of Action

5.1 Current Status
The LDG performance data has been put into a Palm OS database and an augmentation of the loadsheet environment is currently under construction. The integration is intuitive and the advantages of the register tabs at the lower end of the handheld screen are maintained.

5.2 Further Proceeding
The next step is the conversion of the RPM data into a Palm handheld database. The know-how of a conversion of any electronic representation of this data is available.
When the data is once available, the interpolation module will be developed.

5.3 Open Items
- Increased crew workload: Idea of a pilot project where the DCS loadsheet infrastructure is maintained.
- New layout of the RPM: Impact on performance project?

 


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Last modified 2002 Jul 24
Copyright © 2000-2005 Christoph Regli