A low-flying military aircraft took a quick trip over Hamilton leaving surprised and shocked onlookers in its wake.

The plane, believed to be a C-17 Globemaster, was in New Zealand for tactical low-level training flights and was part of Operation Southern Katipo in the South Island.

It has been spotted over Marlborough and Nelson and was seen flying around Kapiti on its way to Ohakea airforce base.

It roared across the Hamilton cityscape on Tuesday and sent Riverlea resident Petra Reiter into a tailspin.

''It was really scary, I tell you,'' she said.

She was driving home from Cobham Dr when the plane appeared ahead of her.

She said it was only 40 metres above ground level.

''I actually saw the plane and it came straight towards us and I thought, oh my god.''

She was not sure what type of plane it was but said it was a passenger jet and was a military grey colour and was quiet compared to other planes.

Her son was also in the car and thought it was in the middle of an emergency landing.

''It looked like it because it was also on its side and it flew farther away and gained height again.''

Far from being a one-off spectacle, Reiter said low-flying planes from Hamilton Airport have become more frequent and her concerns were growing that their peace would be spoiled by the excessive noise.

''Seeing it today was just another thing. You wouldn't want to see it coming down in your backyard,'' she said.

''We're definitely annoyed about the noise as well. We never used to have a lot of noise here and now we regularly have planes flying straight over our backyard.''