** British aircraft services BBA Aviation -c.2% &among FTSE's biggest midcap losers
** Q1 rev falls 6% at constant currency, adj for lower fuelprices & before acquisitions, due to softer-than-anticipatedmarkets & unseasonably warm weather in the north eastern U.S.(impacts de-icing biz)
** Management however strikes upbeat note, says co has gotoff to a good start & trading in-line with expectations
** Liberum calls underlying rev decline "hardlyencouraging", adding there is continued downside risk fromsluggish end-market growth and weakness at co's ERO, ASIG units