This won't work!
Petitions are a notoriously ineffective means of putting across a case to the government. An online version all the more so: it will be easy to ignore, not least because plainly very little effort is involved on the part of those signing their names.
What does occasionally work is enlisting the support of MPs who can take up your case with the appropriate government department. A brief, personally drafted letter (ie not a mass production round robin) is more likely to have the desired effect.
It is alleged in this case that the government had indicated that the inclusion of airfields from the draft wording of the bill was an oversight which would be corrected. If anyone can produce evidence that an undertaking was given it would make it that much harder for the government to wriggle out of this one. Anybody?