Your delay appears to due to an aircraft swap, which probably stems from an aircraft being out of service for maintenence or some other issue.

In other words, your plane is scheduled to fly Denver-Akron-Denver, leaving Denver at 1:00pm. For whatever reason, the plane which would be in Denver at noon or so to head out to Akron at 1:25pm is not available to do that. So instead they are using a plane coming in from Milwaukee at 3:44pm. They are planning to turn that plane around and head for Akron around 3 hours late. That's why your CAK-DEN flight is so late.

If you'd like to follow it during the day, the plane is currently in LaGuardia and will fly LGA-MKE-DEN as flight 371. Then the plane will fly DEN-CAK as #499. The nice thing about Frontier is that by virtue of the animal tails being displayed on their filght information, you can confirm what plane it is. And...if you watch the filght information through the day, if you suddenly notice that the animal for Denver-Akron #499 is different, then they have changed the swap and your times might change.

Will your flight run tonight even being so late? The odds are very good. They know about this delay far in advance so they will make sure there are no crew time-out issues...this is a simple out-and-back flight. It's not like a crew is mid-trip and there's an unexpected delay that burns their active duty.

And finally, although this is no guarantee of course, Frontier rarely cancels and usually has among the lowest cancel rates. For March, which can have plenty of snow and ice events in their hubs, Frontier only canceled nine flights the entire month. The cancelation rate of 0.1% was the best reported, compared to the industry average of 1.3% cancelations. So the odds are in your favor.

Hopefully you're only flying as far as Denver, because it's very unlikely people will make any connections that late in the evening.

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