I had to fill out paperwork for fire trucks the tower sent out (not requested by me..)-once when I was unsure about my gear and the other time when I stated that I had a rough engine. No deviation from any FAR.As I have mentioned-not declaring an emergency gets me the same service,and I have been told (by several instructors/controllers)officially declaring can cause not only paperwork on everyone's end, and possible FAA interaction-if you are working for a commercial carrier I am sure there is someone who takes care of all that-GA drivers are probably more vulnerable. Since stating what your problem is,is very accurate, and still gets the full attention, (all of what you have mentioned has occured every time-full attention, priority)-seems to work fine. I personally would reserve the "e" word for an off airport landing/engine failure. Also, if flying vfr and not getting vfr flight following, which I never do. If you are in positive control with a controller-no reason to squawk emergency-they already have you-and they are already talking to you. If they didn't give full attention/service,and I felt safety was compromised, I would obviously declare an official emergency-just haven't found it necessary-got the same results-safety not compromised,and everyone seems happy at the end of the day.http://mywebpages.comcast.net/geofa/pages/rxp-pilot.jpg

NickI must admit I dont like to declare an emergency. A month back I was flying a Citation at night out of London going to Majorca. Passing FL240 over the English Channel a burning smell followed by accrid smoke pouring out of the air vents forced me to make a request for an immediate return to Biggin Hill.We were asked for the nature of the problem and and on hearing the problem were given a direct course and descent towards Biggin.The Controller asked whether we wished to declare an emergency. As the level of smoke was diminishing the controller accepted a precautionary emergency but in reality we were handled as an emergency.Two weeks before that in the same aircraft at Dublin we had no nosegear showing on the approach.We didnt declare an emergency but discussed the problem with ATC.We made a fly past for a 767 to watch us and to check the dangly bits and then we flew off into a holding pattern while we carried out retraction and extension tests.Finally we had all three greens and made a normal landing. We felt all along that the problem was a contact problem and not a gear problem as such, although on landing we had half a dozen fire engines waiting for us ;-)Like Geoff I have had my fiar share of problems including one full engine failure and two partials and to date have never said those dreaded words "Mayday, Mayday, Mayday".I think its a little dramatic and over the Top. I would rather the Phrase was changed to "xyz is declaring an emergency".I am not alone or unusual in this reluctance as most pilots I know are also very hesitant in saying those three words :-)In most GA aircraft the passengers are much closer and involved with the operations at the sharp end.They hear all the TAWS warnings all the buzzers and whistles and even some of the pilot conversations.Even in small jets this is the case and it is important not to frighten the passengers more that need be.In the smoke incident I am sure they all thought they were going to die anyway.We both turned around every thirty odd seconds with fixed cheesy grins. We peared through the fog to instill a level of confidence in our passengers that we werent really that bothered.Peter