The only flags you would have to flag for deletion of wrong answers (mod notice aside) are very low quality (VLQ) and not an answer (NAA).
NAA should be used in cases where an ‘answer’ is actually not an answer. For example:
So how did it work out, did you need to show your visa?
I have the same problem, please help.
An attempt at an answer should not be flagged as NAA. Providing a wrong answer is clearly an attempt at an answer. Thus, NAA would not be a good flag choice.
The VLQ flag should be used if a post is not readable or understandable (by the average English speaker). It’s basically ‘I can’t really tell whether it’s an answer or not, so let’s just flag it.’ It is only available on new posts scoring zero or less. Examples:
Ich kann zwar kein Englisch, aber die Antwort ist zweiundvierzig.
Wiff fork kite edit theory yes seven nice
Again, while it may seem that a wrong answer is low quality, the description of the flag actually says:
This answer has severe formatting or content problems. This answer is unlikely to be salvageable through editing, and might need to be removed.
I’m pretty sure that a large quantity of users got confused by this wording at one point or another in the history of SE. I’m one of them. Taking the flag declining reason Roflcopter provided, however, it should be clear that ‘content problems’ should mean ‘this might look like English but it doesn’t parse as an English text.’ Therefore, this flag is also not appropriate for wrong answers.
All things considered, there is no adequate flag and thus wrong answers shouldn’t be removed. They should, however, be downvoted to show that they are wrong.