Enjoyable, despite being a typical "Hollywood Blockbuster" I enjoyed this film because I am really into aeroplanes and like to get an aerial dogfight fix from time to time.
BUT, this is your typical Hollywood blockbuster, full of cardboard characters, ridiculous looking CGI effects and ludicrous plot holes.
This is loosely based on a real story. There was a real squadron of mostly US Pilots flying for France. There was a real black US Fighter pilot flying in France at that time (not in the actual squadron) and someone really DID have a Lion for a pet.
But you basically get everything you expect of this type of film. Hackneyed, clichéd stereotype characters, ridiculous romantic subplot, silly implausible flying sequences, and of course, ridiculous amounts of historical inaccuracies.
The Germans all flying Red Baron style Fokker Triplanes I think has been explained as making it readily easy to identify between the French and German planes, but I think that's the usual Hollywood trick of treating your audience like morons.A French Nieuport 17 and a German Albatros are sufficiently different in shape and standard colouring that most audience members NOT familiar with planes could still tell the difference. That is far from the only anachronistic thing in the film either.
I own the DVD (paid £1) and the special features shows that the director actually filmed footage of real WWI Aircraft flying. Why he bothered is a mystery because he completely ignores all this for ridiculous physics defying flight characteristics in most flying sequences. While they are enjoyable and a non plane buff might not notice, they do come across more like a video game than anything approaching real life.
The Romance is mired by the implausibility of how quickly the French woman learns English, and the fact the US Pilot seems to be able to use his plane to just go off on a whim for a tryst with his loved one but is otherwise believable.
Other characters often do some really out of character and implausible things too, but the pilot landing his plane in the middle of No man's land to rescue his friend without first strafing the German trench from the air to minimise the amount of shooting in his direction and then cutting off his colleagues hand rather than just digging out enough dirt to free it is one of my favourites.
Some of the acting is actually quite good, notably the ever reliable Jean Reno as the Captain and Martin Henderson as the veteran pilot. The Chivalrous German pilot is a nice contrast to the "evil" one and the racism stuff is dealt with well and succinctly. Implausible though the flying sequences are for the most part, there aren't TOO many actual explosions and they are enjoyable to watch, but they are interspersed with the slow dragging romance.
Basically it isn't an awful film, but it's not really a good one either, and if done properly, could have been so much better. If you love Michael Bay Films, you'll probably like this, or if you are a plane junkie who wants his flying fix,or a bit of a laugh, or both, then it's worth watching, otherwise, probably best to stay clear.