Approaches, Traps, VNAV and other problems.
As some of you will know I have been conducting a review of the
Universal documentation in order to better understand the issues
arising out of VNAV. Some of our operators use it and some forbid it.
Horizon, Porter and Air Berlin make use of it in all aspects, I am
told. Flybee do not, Tyrolean do not. Some of the issues may be related
to history, to software load, configuration and hardware
variations. I am attempting to get better documentation in that
What is clear is that we do not fully understand how to use the FMS
ourselves, and that is because Universal do not have accurate clear
concise documentation on how their system works and their training
program reflects these issues. We have a limited SOP based on our
limited understanding. The purpose of this paper is to open a dialog in
order that we may all come to a better understanding.
Universal provide two documents. They are the Operators Training Manual
and the FMS Operators Manual. The Operators manual is a generic
document covering numerous variants. Universal advise it is not
intended to be detail specific. It is the document carried on board the
aircraft. It is, as they say, misleading in some areas. The
Training Manual is undated, ever changing, poorly organized,
appears to be unedited, grows by "topsie", and wrong.
I have, with Harlan's help, been corresponding with Bob Bruce of
Universal trying to get agreement on operating specifics and have had
some success. Dave Killin and I have been filming some of the issues.
We hope to be able to confirm some of the operating specifics in the
simulator as I understand the simulator uses a Universal box, the
only aspect simulated is the positioning. Adam at FSI has
been involved as has Bruce Ofstun at Horizon..
I have taken the bulk of the training document and reorganized it into
a 'sequence of flight' format, editing out the superfluous, redundant,
repetitive and non related 400 material. It is presented as a web based
hyper linked document
in a numbered table format. I have added photos from the 400 where
necessary- they are from the Blackberry and of limited quality - but
something is often better than nothing or erratum. It is a work in
progress - any input is appreciated. A listing of the FMS displayed
Messages and Annunciators and the VNAV error messages-will be extracted along with some reboot material and added to the Caution/Advisory/Reboot review.
The issues with the FMS come into clear focus when employing VNAV in approach and is this in this area I will concentrate.
Fundamentaly there are some 5 means of arriving at an airport within the FMS. They are:
1) Enroute Nav. function which may or may not employ a VNAV /v path function,
2) Approach Nav. with VS /Alt sel Function without VNAV/v path reference.
3) Approach Nav. with VS/Alt sel function with reference to VNAV v path.
4) Approach Nav. /VNAV
5) Approach Nav. / Pseudo glidepath.