XSLT concatenate input from several nodes in a single output - sorting

Question

I'm trying to work out a transformation that will process an input with several Flights with Departure and Arrival into a single output with the complete route for the flights.
Input is as follows:
<FlightTrip>
<flights>
<departureAirport>
<airportCode>LocB</airportCode>
</departureAirport>
<departureTime>2013-03-28T10:00:00.000</departureTime>
<arrivalAirport>
<airportCode>LocC</airportCode>
</arrivalAirport>
</flights>
<flights>
<departureAirport>
<airportCode>LocA</airportCode>
</departureAirport>
<departureTime>2013-03-27T15:00:00.000</departureTime>
<arrivalAirport>
<airportCode>LocB</airportCode>
</arrivalAirport>
</flights>
<flights>
<departureAirport>
<airportCode>LocC</airportCode>
</departureAirport>
<departureTime>2013-03-30T14:00:00.000</departureTime>
<arrivalAirport>
<airportCode>LocD</airportCode>
</arrivalAirport>
</flights>
</FlightTrip>
The desired output would be this:
<FullTrip>LocA LocB LocC LocD</FullTrip>
I've tried to use foreach inside the output variable but I can't get it right. I also need to sort the input based on the departure date as the Flights can be in a different order (as per the sample input).
Any ideas of how to achieve this?
Thanks a lot!
Bruno

Answer 1

<?xml version="1.0" encoding="UTF-8" ?>
<xsl:transform xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
<xsl:output indent="yes"/>
<xsl:template match="FlightTrip">
<FullTrip>
<xsl:apply-templates select="flights">
<xsl:sort select="departureTime"/>
</xsl:apply-templates>
</FullTrip>
</xsl:template>
<xsl:template match="flights">
<xsl:value-of select="departureAirport/airportCode"/><xsl:text> </xsl:text>
<xsl:if test="position()=last()">
<xsl:value-of select="arrivalAirport/airportCode"/>
</xsl:if>
</xsl:template>
</xsl:transform>
Will produce:
<FullTrip>LocA LocB LocC LocD</FullTrip>
Working example

Answer 2

Thanks to Joepie for the enlightenment. I had to modify it a bit to get it to work in my environment, ended up using foreach as below:
<xsl:template match="/">
<xsl:variable name="locations">
<xsl:for-each select="/FlightTrip/flights">
<xsl:sort select="departureTime" order="ascending" data-type="text"/>
<xsl:value-of select="concat(departureAirport/airportCode,' - ')"/>
<xsl:if test="position() = last()">
<xsl:value-of select="arrivalAirport/airportCode"/>
</xsl:if>
</xsl:for-each>
</xsl:variable>
<FullTrip>
<xsl:value-of select="$locations"/>
</FullTrip>
</xsl:template>
When applied to the example produces the output below:
<FullTrip>LocA - LocB - LocC - LocD</FullTrip>
Thanks again!