Which website do you use to check on-time stats for flights?

I use www.flightstats.com.

I use flightware.com.

Nothing wrong with LOT Polish Airlines (in some cases, it's arguably better than riding on United).

I am with JHK. What difference does this make with your ticketing process? On-times are simply averages. Very little meaning for a specific flight.

Frank, I'm booking an award ticket and have two main options. One has a 2 hour layover in Frankfurt and the other has a 5 1/2 hour layover. I thought maybe if a flight showed that it is often late, I wouldn't risk the 2 hours layover.

I don't know the rules for award flights. Are both flights with awards? What are your chances for getting on another flight if you miss your connection? Are there several more flights on the same day? I would be comfortable with connecting flights on the same (paid) ticket if I knew that there were additional flights that day that the airline could put me on. If I had separate tickets, I'd be leery of a 2-hour layover after a long-haul flight . . . my reasoning is that the longer the flight, the more likely it could be late. Plus, the more nerve-wracking to be on that flight if it's been delayed in takeoff or in flight.

I don't know the rules for award flights. Are both flights with awards? What are your chances for getting on another flight if you miss your connection? Are there several more flights on the same day?

With award flights, there is a greater risk, even if on the same booking. The difference between paid and award flights is subtle: The deal is, if you miss your connection, they still need to get you to your destination (just like with a paid ticket), but with two important differences:

1. They are not required to put you on the next available flight to your destination. They are required to put you on the next flight to your destination that has available award seats open. On popular routes, that could in fact take days. Now, that's the contractual requirement; in practice, many airlines will "open up" award seats for you in this case, trying not to strand you overnight (or for a week). But they are not required to do that, it's (sometimes) done as a goodwill gesture, but not guaranteed.

2. They will try to find you an available award seat to your destination ASAP, but they may (and often can't) find you a seat in the same class. If your award flight is in coach, probably not an issue. But if you have a business class award ticket...that's another story (or could be). For example, if you have an award seat in business class, and you miss your connection, they have no obligation to find you another business class seat on the next available flight. Available business class seats, on award tickets, are generally scarce, and often are impossible to find for same-day flights. They would likely offer you a seat in coach, which you are free to accept or decline. If you insist on an equivalent (business class) award seat, you might be waiting a long time for a free one to come along.

Now, those are the "rules" -- at least for most airlines, generally. Each program is different, with different policies, and of course, exactly how closely staff follows official policies (or bends the rules for you) varies tremendously.

As an example, I once had an award flight coming home, from Yogyakarta (a city in Indonesia) all the way home to Seattle (via Jakarta, Singapore and San Francisco). I missed the first leg of that flight to Jakarta (there was a major volcanic eruption where I was, and the airport was closed for a full day; so not my fault, legally classified as "an act of god" - I took an all-day train across the island of Java to reach Jakarta). As I got there a day late for my outbound flight, technically, my entire ticket home could have been canceled, stranding me in Jakarta, possibly for many days waiting for an available seat home.

Adding to the tenuousness of my position: this was an award flight booked with United miles, but the first 3 legs of the flight (to Jakarta, Singapore, San Francisco) were all on Singapore Airlines (a United partner), only the last leg (from San Francisco to Seattle) was on an actual United plane, so I wasn't dealing with United Airlines. I was at the mercy of Singapore Airlines when I showed up in Jakarta, a day late for my onward flight out to Singapore. They could have just shrugged and told me it wasn't their problem. But the volcano had disrupted travel across the region, and they were being generous. I did have to wait in Jakarta for another 24 hours before they could get me on a flight to Singapore, but they gave me a voucher for a free night in a fancy hotel there, and honored my ticket all the way home.

The point is that if you are on an award flight, and you miss a connection, you could be out of luck, left stranded for a while, needing to rely on The Kindness Of Strangers. In my case I was lucky that Singapore Airlines was in a charitable mood. Did I mention that I now love Singapore Airlines and go out of my way to fly them if I can, and probably always will? YMMV.

Good luck!

Oh, and to your specific conundrum...

Frank, I'm booking an award ticket and have two main options. One has a 2 hour layover in Frankfurt and the other has a 5 1/2 hour layover.

Given how busy FRA often is (I barely made a 2+ hour connection there last time I went through there), I would not take the 2-hour layover. I am much happier to spend 5.5 hours killing time in an airport knowing I have the seat and I'll get there. I do not enjoy the stress associated with all the "will I make it?" uncertainty.

Two hours is not a lot of time if you have to go through immigration in Frankfurt. I wouldn't risk it. And unless your final destination is outside of Schengen, then going through immigration will be required.

Thanks, David, for that great explanation. That right there helped the decision. And even if it was a paid ticket, what with airlines flying pretty full now, even if there is another flight that day, doesn't mean I'd get on it. And I really don't mind extra time in an airport for peace of mind. I appreciate everyone's thoughts! And thanks for being my "travel family"!

Just booked a Lufthansa flight (United miles) with a 5 1/2 hour Frankfurt layover (from LAX to Venice). Coming back from Ljubljana, I have only 2 hours in FRA but it's an early morning flight, so taking the chance that all will go well!

Our experience is contrary to David's posting. We use United all the time. Our experience is that once we are ticketed with an award ticket it is treated just like any other ticket. Over the years we have missed a couple of connecting flights and were booked on the next available without any question. Once our original flight on Lufthansa was cancelled for equipment reasons and I expected a lot of trouble getting rebooked since it was an award ticket. But the status of the awarded ticket was never questioned and we were rebooked for the following day. This was a 747 with one flight a day from Denver so I thought that it would be impossible to get on anything within the next week or so. That was a couple of years ago so maybe the rules have been changed but an award ticket and can only be rebook for another award seat doesn't make a lot of sense. It could be impossible to rebook for some time if depending on award seats.

Frank, it is my understanding that the rules say if you miss your award flight, they only have to accommodate you within what's available for award seats. That doesn't mean they won't do you a favor and try to find a seat for you, but I'm pretty sure they don't have to.

Our experience is that once we are ticketed with an award ticket it is treated just like any other ticket.

That may be how things feel, but on an award ticket, you are low priority for when things go sideways. With flight delays/cancelation, award flight travelers will generally be at the bottom of the list for fixing things. Those with "elite" status, and those with paid tickets will get priority. Airlines generally know a lot about their passengers (a lot more than one might expect) - things like how profitable they see you (do you book a lot of business travel? or just cash in your miles once every couple years? Gate agents and even flight attendants have that info at their fingertips, and may use it to prioritize things). Of course, when everything's going well, you should expect to receive the same treatment from staff as any other passenger. Even though I've flown a lot of award flights, I've never felt like a second-class citizen by any airline (at least no different from those around me).

Worth noting, the airlines' obligation depends on why a flight was missed...

Once our original flight on Lufthansa was cancelled for equipment reasons and I expected a lot of trouble getting rebooked since it was an award ticket. But the status of the awarded ticket was never questioned and we were rebooked for the following day.

In that case, it was the airline that caused you to miss your flight (you have no control over maintenance issues), so they have an obligation to get you to your destination just as they would for a paid flight. Had you simply missed the flight (due to your own fault), their obligation would have been more limited (they still need to get you to your destination, but they're not obligated to make you as high a priority).

It could be impossible to rebook for some time if depending on award seats.

Yep, that's right, it could. Especially on a route without lots of options, or when flights are very full (and overbooked). As I said, them's is the rules. Fortunately, there's usually a lot of slack in the system, and even when there isn't, airline staff will often have mercy on travelers and will do what they can do avoid stranding someone far from home for a long time. But in a pinch, when things are both messy and also crowded, they may not be able to accommodate everyone, and in those cases, award ticket travelers typically are the lowest priority, and they are not going to bump a passenger who paid money for their ticket to find a seat for you who have traded in your miles for that seat.

I fly United quite often as well. And although I have some quibbles with their program (eg the multiple large devaluations in the past few years), theirs is still one of the better programs for US-based airlines IMHO.