The startup I co-founded (Adioso - YC W09 [1]) tried to do it, including having discussions with a travel insurance provider about offering "layover protection" - so that if one leg was delayed causing you to miss your onward leg(s), your costs are covered. Kiwi.com does this now.
We worked on it from about 2008 till 2013 then basically gave up, as it was too hard to offer a service that customers could really love and trust. (It wasn't for nought; the technology we developed was valuable, and the company was able to rebrand and pivot and now does important work for airlines to optimise loads and fares [2], though I left when the rebrand/pivot happened).
The thing that makes it hard to do is it's basically impossible to get all the flight inventory, including fares and seat availability, that's complete and up-to-date enough to deliver a service that customers can trust.
The engineering challenge is one thing - solving a multi-dimensional travelling salesman problem (price and distance/duration) highly repetitively - but you can solve that with enough smart engineers and "compute", which ITA did in the early 2000s, and on a smaller scale, our team did a decade later.
But you could build the most beautiful routing engine the universe has ever seen, and still have a user experience that's kind-of garbage because the industry just keeps the flight inventory data so locked down.
These days there are APIs and feeds available from the major distribution platforms - Sabre, Amadeus and Travelport, but it's still not comprehensive. You often still need to negotiate individual agreements with major airlines in order to be able to publish and sell their fares. And even then, many of the low-cost airlines (which are often most of interest to travellers who want to find the cheapest route and deal with self-transfer) are not available through these distributors, and some, like Southwest, have blanket refused to be on 3rd party search sites, only starting to relax that position very recently and only with the dominant platform [3]. Kiwi.com has only recently come to a partnership agreement with Ryanair [4] after being in legal battle with them for years [5]. (I hate the thought of having to be at war with your most important partners).
Others have mentioned Skyscanner, which was always the closest to us in what we were each trying to offer (we talked briefly with them about being acquired by them).
Right from the beginning when we got funded for Adioso, my mind became fixated on the thought "if only you get every single flight in the world loaded into one big graph database, what could you do with it?", but it turned out to be a very big "if".
Sorta, the real pain point is if anything needs changing on any of your tickets, it's a total PITA. I value 'less hassle' more than I do saving 5-20% of the airfare. For me Kiwi (and other middlemen like it) are a hard 'No'.
The savings can be a lot more than 20% - last month I had a roundtrip ticket of $2000 brought down to $1300 (and got there faster!) via the switching airlines approach. It did come with some additional stress - needed additional visas and was worried about missing flights.
If things go wrong with Kiwi, they're likely to go very wrong, yes...but on the other hand, if I can keep saving $700 per trip, I can afford for them to go very wrong sometimes and still come out ahead.
This is true when going through any third party portal for either flights or hotels.
No reasonable amount of savings is enough to convince us to ever use a third party portal.
My wife and I travel a lot as a hobby - mostly domestically with one or two international trips a year - and something is statistically going to change between the time we book and the time we fly on at least one of our trips.
It’s a lot easier to make changes directly with the airline/hotel especially when you have status than going through a portal
Just last month we had a flight to Vegas + hotel over Labor Day that we changed at the last minute to go see my mother in law who had been taken to the hospital by our older (adult) son. We were able to change our flights to another city (ATL instead of LAS) as an even swap.
This was Delta airlines.
Then two hours later we found out she had Covid and decided against it and were able to call and change our flight back all without any change in fees and get our hotel reservation back.
Good luck doing that when booking through a portal.
Delta is not perfect, but compared to United and American it’s practically Singapore/Emirates vs Spirit/Ryanair. The whole experience is better in every way.
May not be everyone’s experience, and if you live in a big hub city for one of the others they might be better. But for me, I only book something else if it will save me a plane change.
We flew Southwest last month from MCO - LAS (we’ve been twice this year) because we wanted to try it and SW has more non stop flights than Delta from MCO.
We knew about the non assigned seats. But flying Southwest without assigned seats is like a reenactment of Peloponnesian War (“We are Sparta!!”). We said we would do a layover before flying SW again.
My wife chose to fly Spirit back to LAS when she went to a conference over flying SW and that’s saying a lot.
And those are two of the worst flying cities in the US. MCO, piles of families that have never flown before doing a once-in-a-lifetime trip. LAS, drunks who don’t know how to keep a lid on it.
I don’t have an issue with SW. The seat thing never bugged me too badly.
But no first class. And if I can’t afford business/first, I can’t afford the trip these days. I would rather stay home.
It's even worse when using points. Amex now uses Expedia on the back end for hotel booking. I made a res for a hotel in Italy and I tried to change it. Amex says call Expedia. Expedia says call the hotel. The hotel says call Expedia. Soooo frustrating. I think Amex travel is going to poop, and that used to be their thing.
Same reason that while I may use Kayak/others for searching, I almost always book the ticket directly with the airline unless it's such a huge savings that it's worth to go through a third party and deal with multiple airlines.
Many airlines will price-match these days so if do find the same flight cheaper through a third-party they'll give it to you at that price (providing all legs were with their airline of course).
My (recent) experience with Kayak is that when you do finally pick a flight to book, it only redirects you to the carrier site where you book it manually. This was once for United and once for Delta. Is that interaction maybe carrier-dependent?
> You often still need to negotiate individual agreements with major airlines in order to be able to publish and sell their fares.
Out of curiosity, what's stopping you from just scraping/crawling this on a daily basis? I'm at a scale-up that offers a BI solution for the hospitality sector, and we scrape well into the tens of millions of data points per day using web crawlers.
They obviously don't want you to, so it's an ongoing cat and mouse game of integrations breaking, but once we we're established and had a customer base, the ability to negotiate data API agreements actually opened up. Especially if you have data to offer in return.
We built the company from the start by scraping low cost airlines, and always did a lot of it.
It’s just a very big undertaking - building all the scrapers, maintaining them (every time any detail of an airline website changed), getting around anti-scraping measures, running servers, and even then your data is out of date as soon as a flight’s price or availability changes. And it’s an exponentially growing undertaking the more comprehensive you want your index to be - I.e, to include round trip and multi-stop tickets.
Adioso was amazing! It was the only flight search engine that let explore possible trips (rather than just looking up flights once you knew where you wanted to go) by searching for regions or "International".
Question for you: can Google Flights (or any other flight search engine) give you the same kind of search capabilities/answers/experience you got from Adioso?
Not that I'm aware of. Google Flights has good data (such as price change data), but it feels like any other search app. Adioso felt more like Pinterest in some ways, where I could have a vague idea of how I wanted to travel, and then explore different trips based on that. Even just big photos (IIRC) of different cities gave some idea of vibes.
I've looked for other booking sites that helped me determine where I want to go, but haven't found anything else similar sadly.
Thank you for sharing this. It’s some food for thought! So much thought and effort went into how the site would feel to use, but it’s very hard to convey the importance and value of that to investors who are not in the primary audience. I still haven’t let go of the idea that we could make it work some day.
It very much came through. Always disappointing when a great product doesn't become a great company, but I hope you get some satisfaction in knowing you built a great product that a lot of people really enjoyed!
The upfront capital costs and fixed running costs are huge, and the commissions are very low - often zero, normally about $1 or $2, only very rarely $10+ if it’s a high-priced purchase (business/first class with multiple passengers, but that’s rare on a budget flight funding site). And because travel is an infrequent purchase for most people, you don’t get much of a retention flywheel.
This is why there are close to zero flight search engines that are successful standalone companies and almost all the big brands have been acquired by bigger dominant players - Kayak is now a sub-brand of Booking (prev. Priceline) and Skyscanner was acquired by Trip.com in China.
Yes they can be valuable properties but more as a traffic generator for selling other products (accommodation, car rental, insurance), and you need a big team to do all that.
Also loved Adioso, while traveling in Europe I used it extensively - the UI was incredible and I could never understand why it was not much much more popular... I haven't traveled much in the last 4 years and it's sad to see it does not appear to exist any longer?
The last few times I used Skyscanner, I was disappointed because their "database" was outdated. When I clicked on a flight from the search results, it took me to the airline's website, which then showed a higher price. Often, there's no official fare from the airline, and Skyscanner lists prices from third-party providers I don't really trust.
I'm finding Google Flights more reliable these days.
I believe (and it's been ~4 years since I left Google) that ITA is one of the data sources, but there are now direct API connections with some providers.
It’s an ongoing tension. Direct bookings are ideal but are only adequate if your brand awareness and loyalty is strong, like AA and Southwest. To whatever extent that’s not the case, you need to be available via partners/agencies and on metasearch sites in order to be found.
Our pitch to airlines when we were trying to establish partnerships with them was that we could find flexible travelers to fill seats that would otherwise be empty, and we had unique ways of doing that (which is why the company was able to pivot to enterprise), but we weren’t strong enough for them to feel the need to partner with us (and they don’t want to help a small player grow into a big player).
Flight revenue optimization is an art and science at least as old as industry deregulation, and funnily enough is now something my old company is providing a lot of help with. If you can’t beat ‘em, join ‘em as they say.
Once an airline schedules a flight, each additional passenger is 0 marginal cost.
Besides the people who have high status with an airline are usually price insensitive business travelers.
The people who aren’t penny pinching customers who do fly often on their own dime are either going to pay for business class or first class seats or are going to get auto upgrades for free once they book. At least that’s how it works on Delta.
They surely aren’t going to sully themselves by sitting in the “cattle class”.
For instance, Delta releases cheap economy seats to their partners like Virgin and KLM. I routinely book short flights between MCO (Orlando - current home) and ATL (former home) all of the time for 5500 points via KLM/AirFrance to fly Delta (cash price $230 one way) and to see my parents in small town south GA (MCO - ATL - ABY) for 8500 points (cash price one way $358).
The tickets that Delta releases to partners are the least desirable times and they take away even tho use three weeks before the flight because they can jack up prices.
As an example, there are at least 15 flights a day between MCO and ATL on Delta. Three of those flights may be available on KLM or Virgin
I've done paid travel for several companyies and they've all still been price sensitive. They usually have some policy where they'll detect some "reasonable" itinerary but then let me choose my own as long as it's within a certain dollar amount of their "reasonable" itinerary.
Who are these "price insensitive" companies?
What's always been especially annoying to me is that I've never had an option to pay out of pocket to upgrade my seat. Company travel portal only lets me book an economy ticket, and if I ask the airline about upgrading, they say to contact the company travel portal, who of course tells me to contact the airline. $eyeroll_emoji
Of course, the companies always have a strict "ALL TRAVEL MUST BE BOOKED THROUGH THE PORTAL" policy, so I couldn't even just pay the ticket out of pocket and get a portion reimbursed.
> I routinely book short flights between MCO (Orlando - current home) and ATL (former home)
Why would I drive 6.5 hours when I can just get dropped off by the airport, whiz through Clear + TSA Precheck, hang out at the Delta lounge where I get free food and alcoholic drinks, hop on the plane and be there in an hour and a half?
Especially since it is essentially free?
Besides I work remotely and we have been down to one car since mid 2020. If either one of us are going by our self, we wouldn’t want to leave the other without a car.
As far as price insensitivity , what are the chances that the cheap routes are going to be available when and where the business traveler needs to go?
I assure you that the travel policies that your company uses for you aren’t the same ones they use for their executives.
I doubt very seriously that Andy Jassy or Bezos had their expense report rejected for a $3 stick of deodorant they charged to the room like what happened to me when I was at AWS (cloud consulting department - ProServe).
But even Amazon didn’t make you choose the cheapest route and I could always choose thier “most preferred carrier” - Delta - even if it did cost more.
I could also choose non stop vs layover if it costs more.
It's a 30 minute drive to the airport, to which I want to arrive 2 hours before departure to ensure I have enough time to go through security. It's never been more than 30 minutes at my airport, but I don't want to chance it. There's also the time it takes to check my bag and walk to the gate. I'll typically get to my gate an hour early.
I don't fly nearly enough to get access to lounges.
Then when I get there, there's the waiting for my bag, then waiting for transportation...
From the time I leave my house to the time I arrive at the hotel, that 450 mile flight would take me a total of probably around 4 hours. I'd rather just add on another 2 hours and drive myself, especially since that means I'll have my own car when I get there. But I enjoy driving, so that likely influences my choice as much as your access to TSA Precheck (I should get that) and the Delta Lounge, not to mention it being free.
One reason I could see is to keep perceived price level for the frequent flyers. If they don't see best deals they won't expect those. And the hardcore deal hunters are not loyal to you or your brand.
Giving frequent flyers very good deals make them expect them, thus not be so willing to pay "regular" price.
Virtual interlining is really dangerous model for them and their brand. It basically means that they would be reliant on someone else without any guarantees in case there is delays or problems.
And with different alliances they already have fully functional interlining model. So trying to extend outside this is not beneficial for them.
Those flyers don’t care. Most frequent flyers are using other people’s money (business travelers) or are not price conscience.
We don’t even compare prices for domestic flights and we fly a lot on our own dime (15x-20x+ a year since mid 2021). We instinctively just book Delta where we have status and lounge access.
They do care when there is no valid routing from point A to point B via official codesharing/interlining/alliance partner airlines on a given day, forcing an overnight layover, or virtual interlining.
Usually this happens when flying long haul business class from smaller airports to another small airport on a different continent.
But that's exactly the opposite of what is happening - allowing third parties to construct itineraries that compete with the ones that are being sold by the airlines results in a competitor; not an enabler; for yield management purposes.
I haven't flown in a number of years, but when I was, it was common knowledge that all airlines intentionally overbooked their flights. If you ended up being one of the unfortunate last 5% (or whatever) to check in, you were effectively turned away and offered a voucher for your trouble.
A friend was bumped on a full flight from London to Europe last week because he didn't check in early enough, but I haven't heard of it happening on the continent side.
Yep, post-covid it seems like airlines are favoring fewer flights that are more packed. I don't fly a lot (couple times a year), but when I do, it's very rare to see a flight that is not at least 95% full.
Yeah, for the routes I've flown over the last 5-10 years, significant numbers of empty seats are very much the exception rather than the rule, and it got worse post-covid.
Overbooking is still an industry standard approach to profit maximization. The opportunity cost of being overbooked (rebooking/refunding) is way lower than having a few seats empty because of the average cancellations.
tl;dr - airlines are happy to sell you a seat that's taken, betting some % of other people cancel.
I still have fond memories of their legendary (pre-leetcode) coding challenges [0] posted on the T (they also hosted the Boston Lisp users group in the early 2000s which was filled with mind-blowingly incredibly brilliant people, everyone there seemed to be an expert in software and had a PhD in some other, non-related field)
Having worked a bit in the travel industry, I highly recommend that you never book through a third party (by all means use their search). Third party apps are not allowed by airlines to charge less than the airline and typically have abysmal customer service, and I can assure you any "add-ons" offered by a third party are ultimately a scam.
Disclaimer: I've worked for the OTA Hopper for 7+ years.
> Third party apps are not allowed by airlines to charge less than the airline
This is not necessarily true. OTAs are not allowed to list a price that undercuts the airline but there are definitely ways for them to undercut the price that the booker ends up paying e.g. offering credits that they can redeem on future flight bookings. In this scenario the airline still gets paid the full amount for the ticket and the OTA makes up the difference.
Airlines are fully within their right to withhold inventory from OTAs that do this, but that entirely depends on the relationship that the OTA has with the airline. In some cases airlines actually run discount campaigns through OTAs in order to capture a bit more market share or fill inventory that they're not seeing being booked through their first party website.
>I can assure you any "add-ons" offered by a third party are ultimately a scam
This is definitely not true. Any kind of insurance product offered by third parties are essentially just that. Hopper's "cancel for any reason" insurance is essentially paying a premium to make your ticket fully refundable. Typically airline inventory managers price refundable tickets at a fixed premium and there's an opportunity there for OTAs to essentially undercut that premium because it's a naive model.
> Third party apps are not allowed by airlines to charge less than the airline
Technically true in that they can't undercut the airline on the same fare class.
But there are many different fare classes and some of them are only offered via 3rd parties, so you can often get much better deals via e.g., Expedia than you can by going direct to the airline.
Just this year my family flew Melbourne-Madrid then Milan-Melbourne, both legs on Cathay, but this route was only available on Expedia (and maybe other OTAs too, I don't remember) - all I know was that it was impossible to even search for this route on Cathay's own website. We didn't have any issues, but if we did I don't know if I'd worry about Expedia's customer service being much worse than an airline's own service.
> We didn't have any issues, but if we did I don't know if I'd worry about Expedia's customer service being much worse than an airline's own service.
The problem (speaking as someone who has to deal with Travel Agents many, many times) is that Expedia will say it's Cathay's problem, and Cathay will refuse to speak to you and tell you it's Expedia's problem.
This has happened to me so many times with both flights and hotels. Now I very rarely book through third parties (only search) unless the discounted rate is compelling enough.
It just happened to me 2 weeks ago. I booked a resort in Cancun through Chase Travel at a heavily-discounted rate and made an error in booking, for one person versus needing two. Chase said they couldn't change it and to call the resort, their middle agency said they couldn't change it, and the resort said they couldn't change it and to call the agent! It eventually got fixed after hours of calling and essentially pleading.
I'm very late to this, but actually it was the resort in this case. The whole process was clearly very undocumented and had a very backroom-y feel to it but they made it happen.
> Third party apps are not allowed by airlines to charge less than the airline
How come I regularly see third-party OTAs offer the same itineraries cheaper than the airline then?
Sometimes there's a mystery fee added just before payment, but not nearly always – and I've flown such itineraries once or twice myself (if the difference was significant and I was absolutely certain I wouldn't need any change or extra service).
I was under the impression that these effectively share part of their agent fee with the traveler as a form of kickback (to appear as the cheapest option in search, which in the end might end up a win-win for both).
One trick they use is to book via a different country. Flight from A to B when booked on the main English website in dollars can be a higher price than the same leg being booked on the Russian website in rubles.
Two reasons for that, one can be because the airline is less known in that market and whats to price more aggressively, and the other is that the ticket conditions are slightly different. For example your right to get compensation in case of a delay (and how much) may be different between those tickets.
One way I've heard is they don't book your ticket immediately but predict when the airline's price will go down and book in then. I imagine they have far better data to enable price prediction than the general public, and can spread the cost of getting it wrong over their other customers.
At least the ones I’ve used have always sent me a ticket number within at most a few hours, and usually instantly. I’d be surprised if that really was a factor these days.
From what I remember from working in the industry many years ago, the process is actually split into (at least) 3 parts.
1. Reservation
2. Booking
3. Ticketing
Each step has its own expiration dates set by the airline, which can range from "instant" to several days/weeks. They may also set different cancelation fees for each step. A smart travel agent could in theory use this to cancel an old booking and book again if the price is reduced, but I think some airlines have changed their practice to avoid this.
Keep in mind that I mostly worked for the European market. I know US airlines operate a bit differently from the rest of the world. They usually have more flexible rules around flights and exchanging of tickets.
>A smart travel agent could in theory use this to cancel an old booking and book again if the price is reduced, but I think some airlines have changed their practice to avoid this.
This is called churn and airlines are pretty on top of it. If you do this often then it will completely ruin your relationship with the airline. Maybe individual travel agencies can get away with it if they're trying to book a handful of tickets each week but OTAs can't.
> I think some airlines have changed their practice to avoid this.
AFAIK even direct connections still use the pattern of creating a PNR, confirming the booking, and then issuing a ticket. Even so in the US, airlines have to guarantee a full refund if a domestic flight is cancelled within 24 hours of booking.
Airlines own systems are often awful UI and in case of some asian low costers your data is immediately sold to spammers (and they collect as much your data as they can too).
Depends on exact case but if traveling on a budget going with low costers and connections a good third party can be better than an unknown shitty airline's system.
I used Expedia a few years back, got a lower price and could cancel for full refund within a day but they probably don't do that anymore. Kiwi seemed okay. Ctrip now owned by China.
I'd be very careful with Kiwi. They don't have official OTA agreements with all the airlines they resell; at least Ryanair at one point was actively hostile towards them, and Kiwi was working with personal Ryanair accounts to get around their roadblocks. This in turn meant I couldn't access Ryanair's mobile boarding passes and had to find a printer on short notice at the airport.
While airlines can apparently not legally completely prevent such "uncooperative" third-party resellers, and I do have some sympathy for the business model, it's not great to be stuck between travel agent and airline when things go wrong.
Other OTAs like Experian actually take the role of a good old travel agent (the entity historically doing much of the ticketing work the airlines are now doing directly) and will usually only sell you itineraries of interlining (i.e. cooperating) airlines, and also only of airlines that accept travel agents as business partners in the first place.
I have bad experiences with Kiwi and ctrip and a bunch of other ones. The support is indeed terrible and if anything goes wrong, the airline will tell you to contact the 3rd party agent... which has horrible support so there you are, stuck somewhere in asia. I had multiple occasions in which I just booked another ticket because of their incompetence, losing a few $100 as I could not take the risk of being late. Now I only book directly at the airline: at that time the company was booking and they just took what google flights gave them, which is often not directly at the airline.
> I still have fond memories of their legendary (pre-leetcode) coding challenges [0] posted on the T
Those ITA puzzle ads on the T (Boston MBTA subway) got my interest. They were so much better for introvert thinkers, than getting ambushed in a Google interview context, and there was also no interference from a bad-loop interviewer.
> they also hosted the Boston Lisp users group in the early 2000s
IIRC, those meetings were organized by Faré Rideau. Volunteering meeting space was maybe ITA (then Google) and Northeastern University?
(I made the small contribution of building the the Boston Lisp announcements email list, by promising a lot of people, wary of social media, that it would be announcements-only. This included famous people, who I'd read about as a kid, such as in the Steven Levy book, or knew only from their names on books and standards documents.)
Incidentally, speaking of brilliant big names in programming... in a few weeks, Gregor Kiczales, Hal Abelson, and Gerald Sussman are speaking at RacketCon 2024. https://con.racket-lang.org/
> Having worked a bit in the travel industry, I highly recommend that you never book through a third party (by all means use their search). Third party apps are not allowed by airlines to charge less than the airline and typically have abysmal customer service,
That’s not always true. I’ve often used services like Skyscanner to find a flight, then checked directly on the airline's website, and the prices didn’t match. Sometimes, it depends on which country you're in too. For example, I once looked at the same flight on Lufthansa’s German site and on a localized version for another country, and the price was different due to taxes. By a third part, I never had a different price depending on which country you are buying it.
However, nowadays, I still prefer to book directly through the airlines, though, because when they cancel your flight—and they’ve been doing that quite a lot since COVID—you have a better chance of holding them accountable.
> Amazingly, the graph diameter is often as high as 20: there are airports that can take 20 flights minimum to get between
I wonder if that's still true. It's hard to imagine. And just the thought of having to optimize that search function made my cortisol levels spike a bit.
> typically this will be a small airport in Alaska or Canada to another small airport in Africa or Indonesia
It's still mind blowing to me. Surely any Alaskan airport would be within 5 hops of Anchorage (or not have scheduled flights at all, fine, but that can't be the case here), likewise surely any Indonesian airport is within 5 hops of Jakarta, and Anchorage-Jakarta can certainly be done in 3 hops in a multitude of ways. But one of those assumptions is wrong by 7 hops!
There aren't even that many airports to consider, the same presentation gives 4000 as the number included in the analysis.
Maybe the graph topology is something like a series of tiny airports that each only connect to the next airport in the series, probably by the same flight that makes multiple stops (not unknown in island hopping, and maybe then in Alaska/Canada too). So you don't really board 20 planes but you do require 20 takeoffs and landings.
It may also depend on optimizations. Potentially you may be able to do fewer hops but if the schedules have 1/week flights they may end up taking 2 weeks calendar time for 7 hops while 20 hops gets you there in 4 days. If the window used for the graph creation doesn't cover enough schedule time, more optimal routes may fall off the edges.
This doesn't match the phrasing in the presentation, I would expect "the graph has diameter 20" to be defined without any reference to the weights of the edges (whether in flying time, total time, cost...)
But it's definitely plausible the author half remembered the routes with 20 hops from some optimized search like this, and wrote the wrong thing in the presentation.
Thinking about it, I bet you can prove this is the topology. If the graph is generally densely connected (almost all nodes have 3+ destinations) then the diameter can't be that high compared to the size of the graph. Proof left to the reader. So either there are chains like described above at the edges, or there's a chain like that separating two parts of the graph (suppose there was only one route connecting the US to Europe, and it stopped in Newfoundland, Keflavik and Shannon). The last possibility is obviously nonsense, though, we know that major airports are densely connected.
Yeah, so far CKX is the airport I can find with the most hops to Anchorage (4, but 3 to Fairbanks which is also fairly well connected). YGZ is likewise 4 hops to Ottawa, and I can't find anything higher in Canada (there are a few that are 4 hops to Montreal in northern Quebec). Nor can I find anything in Greenland more than 4 hops from Copenhagen, Keflavik, or Gatwick (hilariously, that's the fewest-hop big airport for some routes due to flying through Akureyri, which is connected to RKV rather than KEF). There must be some island hopping chain somewhere in the Pacific (or perhaps in the Indian Ocean?) but it's not so easy to find. It seems you're usually a few hops from either Tahiti, Hawaii or Fiji...
I have heard about some routes in northern Norway that have a lot of short stops to pickup/unload passengers (like a flying bus). I don't know if they still exist
Has to be worse than that. 20 is still way too many degrees of separation if every region operated on a hub and spoke model.
I would imagine we're seeing two to four groupings of sequential routes which are subsidized access. A floatplane which hits every island in the archipelago, like a bus route, before reaching the international airport with jets. Likewise with bush planes in Arctic villages, and regional turboprops that hit a sequence of rural airports because they only attract a few passengers a day on their entire route.
Never book anywhere else but the airline website. It's not worth it, these days. There might be some deals but when and no longer if, IRROPS happens you will face an uphill battle to fix your problem playing a triangle between the airline and the OTA you booked with. Flying has changed: past covid and Boeing-being-shit-revealed there are not enough long range planes, in Europe because of the Ukrainian war Hungarian ATC is overwhelmed which creates ripple effects all over and nothing is on time. And that's just the regions I know about. https://travel.stackexchange.com/q/174173 has more.
One search feature I wanted was a way to look up a list of all flights leaving an airport on a certain day.
In the early stages of vacation planning, it’s be fun to see a list of all possible direct flights to evaluate my options, but the use case of doing flight searches with an unknown destination isn’t too common. Basically, i want to be able to browse flights like a bus schedule and just see what the possibilities are from a particular start point
Google Flights does this really well - just leave the destination empty or use something generic, like Europe/USA. I do this all the time to find new places to go to.
You can get something similar from https://www.kayak.com/explore/ except the results are shown on a map rather than as a list: you specify an origin (and optionally a departure date) and the map shows price icons at all possible destinations.
You could use flightaware.com for this. Just search a date and a departure airport. The caveat is that the list will be fairly large, with a lot of repeats.
tomhoward is correct. It's called "virtual interlining". I started the team that built it at Hopper (started working on it in Fall 2020 and we launched our first version in Fall 2021). They're called Mix & Match fares on the Hopper app. It's a really hard problem. So hard that we didn't even try to solve the "best" flight. We used a bunch of heuristics to find what we believed would be "better" flights. We measured what we called "beat rate" which was the rate that a VI flight was the cheapest on our flight list. When I left the team, our beat rate was around 0.5 (so a VI flight was the cheapest half the time).
Adjacent plug for a free Chrome Extension: FlyOnTime embeds flight delay probability straight into Google Flights. Very useful when you're evaluating a number of flights from the same origin and destination but at different times.
One use case I’d love to see is the ability to find the best price for multiple city tickets.
I’m fairly flexible on dates, but getting the best price for it is a super iterative process. Having some similar functionality like excel’s solve function would be awesome to find optimal dates within a range for each destination.
In my experience, these tools have lost their value in the post-COVID world because the airlines have (a) collectively hiked their prices, and (b) have slashed and otherwise aggressively changed their route structure.
I spent many a happy hour <2020 on ITA Matrix. It was well worth learning as a tool back then despite its terse interface and tricky syntax.
But these days? The sorts of clever tricks you could do before are no longer viable for the reasons I outlined at the top, i.e. connections no longer exist and/or the price is no longer attractive.
And before anyone tries to tell me otherwise, my experience is bang up to date. What I said above is based on 2024 experience.
During COVID when nobody was flying fares dropped.
But today fares are the lowest they've been in the history of aviation, except for during COVID which should never be factored into trends.
Inflation-adjusted averages for fares, both overall and on specific routes, for the last 30 years are here: https://www.bts.gov/air-fares
Even with fees and taxes airfare is the lowest it's ever been.
Internationally the difference is even greater than the halving of US domestic ticket prices over the last 30 years.
The tricks no longer work because the bottom has been reached and there are no more pennies to pinch.
If one buys a ticket today, right now, for next month one can fly from DC to LA for $98-- round trip. Then they will complain about paying $30 for a bag....
I can fly first class from New York to Frankfurt for less than what an economy class ticket cost when I was visiting my Oma in the 80s and 90s and that's NOT adjusted for inflation.
> But today fares are the lowest they've been in the history of aviation,
What planet are you living on ? Clearly a different one to me.
As I said, I speak from direct experience.
Before COVID, I could regularly pick up J-class (business) fares on top-quality airlines for 2–3k a pop.
Post-COVID for J-class you'll be lucky to get much change out of 7–8k unless a specific airline has a sale on.
Prices have gone up. That's a fact. I travel enough for business and pleasure to know that. And its the same with my friends and acquaintances.
Sure, if you're looking at the bottom of the barrel end of the sector where the LCC's operate then prices are still cheap. But tools like ITA Matrix were never useful for bottom of the barrel flights, you always just went directly to the website of whichever horrid cheap and nasty operator.
> If one buys a ticket today, right now, for next month one can fly from DC to LA for $98-- round trip. Then they will complain about paying $30 for a bag....
LA<->DC is my most commonly booked flight and I haven't paid less than $300 (net baggage fees) in almost 20 years. On top of that, I end up with less legroom than I did 20 years ago.
BWI is not DC, I don't fly Tues-Tues, and 20 years ago I was paying as low as $150. Flights now are cheaper than for most of that time, but after you adjust for inflation and paying for bags, they were definitely cheaper in the mid-late 00s.
I have long wanted to build an engine that let's you book a vacation on points. You connect all the points programs you have and it shows you how to leverage them to get the best deals on flights and hotels. The trick here is that you can transfer points from credit cards to some airlines and hotels, and sometimes the points are worth more when transferred. But, integrating with all these systems is the problem, and it's a big problem. Especially since there is no way any of the players want this to happen. Maybe it could be built as a browser plugin?
There are a number of sites that do this that have been released in the last few years. https://www.pointsyeah.com is probably my favorite since their free offering is very workable.
I've never understood the comments on all of the posts like this advising people to never book via a third party. Is it an American thing?
I've probably been on around 250 flights in the past 7 years in Europe and I can't remember one time that it was cheaper to book directly than through some third party. Sometimes it's the same price to book direct, but it doesn't matter either way: the support you're going to get is the same, and the insurance or whatever depends on... exactly whatever you've paid for already.
I think this is not true. In my limited experience, if you book a flight through a third party or even a code share agreement, you don’t get full access to the flying airline’s UI and things like changing your flight or dealing with cancellations are a real hassle.
Just last week I had an issue where I had booked an Iberia code share flight through American Airlines, but then Iberia bumped me from the flight onto an AA flight. Of course, both Iberia and AA support initially claimed it wasn’t their problem and that I needed to contact the other airline.
Maybe in Europe it’s not as much a problem because (1) modifiable flight tickets aren’t as common and (2) passenger rights in the case of delay and cancellations are stronger.
Yeah, due to thw Fly America Act, I (usually) have to book through a US carrier even if it's a code share for work travel and run into this problem often...
It's often slightly more expensive to book direct but if you want to e.g. buy extra baggage at a discounted online rate (i.e. not an airport mugging), there is no guarantee that a third party will have a UI for that.
I've also never booked a flight through one of the 3rd parties where I couldn't access the booking on the airline's website.
Some time again (as discussed in this thread), Ryanair had some spat with resellers. So I had to upload a picture of my ID to the Ryanair website in order access my booking that way.
The leading response does a good job calling out that this is pretty risky for the traveller. Similar to skip lagging, if anything goes wrong you can end up is a pretty difficult position.
Even if you have insurance that can cover the cost of the low cost connection ticket you just missed.. try buying a new ticket at the airport for that same day or same week even and you’ve now spent more than getting a regular ticket in the first place. And that regular ticket airline is responsible for getting you to your final destination.
I did some extreme budget flying as a youth and you might just get stranded at a random airport so you better be very flexible with your plans. If it’s inside the US maybe you’re fine to rent a car or take a bus or something but if you happened to layover in UAE or something then it gets trickier
Google built something amazing in Google Flights [1] (and they haven't ruined it yet).
It's no-nonsense, easy to filter by number of stops, and 'date grid' is great for scoping out savings by departing a day or two earlier/later without having open multiple tabs as other sites necessitate.
Only criticisms are extremely mild ones: it defaults to 'return', doesn't remember your currency, and bizarrely defaults to a month ahead for the departure date (actually, they must have very recently fixed this because it doesn't do that anymore!)
My biggest criticism of Google Flights is that sometimes the price it shows you is only available through some sketchy third party OTA based out of a foreign country that only offers support through email. Good luck if anything goes wrong or needs to be changed with your ticket.
Fun fact: sometimes Google Flights will show a (lower) fare on United that doesn't exist on United's own site. But if you click though to United from Google, it magically now does exist, and can be ticketed. I don't know if this happens with other airlines (I look for and book mostly United).
I've used Google flights ~50 times and hadn't seen too many recommendations for flights booked through OTAs, but hard agree with avoiding them (and booking directly with the airline).
They can; this usually shows up with a remark of "separate tickets".
There are considerable caveats when doing that – it's generally not advisable for connecting flights (you're essentially on the hook for missed connections etc.), and even just for separate outbound and return tickets it can mean trouble (e.g. if the outbound flight is cancelled, there is no obligation for the separate ticket to be refunded to you).
Granted I only travel with hand luggage, I never had any issues with cancelled or delayed flighs when booking separate tickets. Even so they are relatvely cheap. It is even cheaper if you book your return flight ticket separately.
You need to be more clear about what you meant by saying "never had issues".
The point is there might be issues because the second flight has no obligation to refund you if you're late (but they might still do out of generosity).
It's not like it's gonna happen all the time. So having data points saying that didn't happen is kinda pointless.
That makes an enormous difference, since you usually can do your check-in online a day or more before departure.
I just had a flight where I had purchased my connections on separate tickets. When I arrived at the baggage drop-off, it was closed and no staff from the airline was anywhere. So I had to bring my big suitcase along through security and then the airline staff at the gate was friendly enough to check it in for me for free.
But if you're bringing anything in your checked luggage that security doesn't like, you will have to just leave that item at the airport. You might also have to pay a high fee to bring it to the gate instead of checking it, depending on airline. I had purchased my ticket directly from the airline, so maybe they treated me better because of it?
Most major airlines support this. Search for "Los Angeles" on Southwest, for example, and you can simultaneously choose from LAX, Burbank, Long Beach, Ontario, or any number of airports across the region.
I worked on this for tripstack a while ago. They offer it through their partners. Kiwi is the other one who made it a thing. Now it’s more common to see it all over.
As explained in the answer, almost always Expedia will issue a single ticket across one or more airlines (the technical term for that is "interlining"), which is different from an itinerary made up of actually separately issued tickets.
In the former case, there's always exactly one airline responsible for getting you to your destination in case of a missed connection or itinerary changes; in the latter case, you're often on your own.
I used Kiwi.com for this a few weeks ago (combining multiple European carriers, including Ryanair) and it worked rather well.
My first flight was delayed, and it seemed likely I would miss the second leg flight, so they sent me an email with a list of options to reschedule. I'd purchased the 'Premium Protection', so I think I could choose a new option up to €250 (+ hotel if overnight) without paying any extra.
I decided to risk taking the first flight, as the second airport was much bigger so figured there would be better flights from there. Fortunately the flight on the second leg was delayed too, so I didn't need to change anything.
What Kiwi.com is doing with their "separate tickets plus connection insurance" model is called "virtual interlining", and it's an interesting alternative in some scenarios (well-connected airports with many alternatives). But I'd still never risk it on an important connection.
I've had a very bad experience with Kiwi.com myself: I booked a Ryanair flight on them without realizing that Ryanair is actively trying to prevent Kiwi from reselling their flights. Kiwi.com apparently works around this by booking tickets on pools of Ryanair retail accounts, to which they don't share the credentials with travelers – making mobile check-in impossible. (And Ryanair at least at the time was charging over 100€ of a "service fee" for a boarding pass print at the airport...)
This is only marginally related to booking separate tickets, but I suppose the larger point is that it's never a great situation to be stuck between the lines of two companies actively hostile towards each other, when you really depend on their cooperation to get to your destination.
"Official" interline agreements are an explicit statement that two or more airlines will make at least some reasonable effort to get you and your luggage to your destination, and will be on the hook for it (under ICAO regulations) if things don't work out.
According to the poster, he found a combo that wasn't available in the online booking system. From what I recall from my time at Travelocity (coming onto 20 years ago, so probably slightly out of date), there are only a handful of GDS 's(Global Distribution Systems), of which Sabre - the owner of Travelocity - was at the time the largest. Those GDS systems are supposed to know about all of the flights from all of the airlines and find the cheapest route across all airlines and for a long time, they did. But as time went on, carriers like Southwest refused to participate with the GDS's and offered direct fares to customers while competitive GDS's sprang up and started to fragment the ones that were being used.
I can't recall exactly which GDS Expedia used (Worldspan or Galileo I think), but I do remember that you could comparison shop between them and us and find lower fares depending on which GDS you were using because they listed some airlines that we didn't and vice versa and even some fares on specific airlines - Sabre was originally an AA subsidiary so tended to have better access to AA fares and was _always_ the cheapest way to fly in or out of Dallas.
So what OP is looking for is what the GDS's would call an uber-GDS - which is, of course, what all of them are angling to become, but are being thwarted by competitive business practices. It's entirely possible that he found a route that was partly available on Sabre and partly available on Expedia that was cheaper than what was available on either, but he had to go poking around for it.
So, why not make a GDS of GDS'es that searched all of them and found combinations like the one OP found? A lot of companies tried - sites like Travelocity and Expedia and Orbitz were online and scrapeable, after all. The problem was, there was no money to be made in them. Travelocity made a lot of its money through travel agency fees - Travelocity acted as a travel agent and got the same commission on tickets that a brick and mortar travel agent would get. I assume Expedia and Orbitz and Priceline did the same. The aggregators, on the other hand, had to charge a fee on top of that to make their site profitable. There are a few people like OP who have a specialized need to be in a certain place at a certain time that an aggregator of aggregators could come up with, but not enough that were willing to pay a fee on top of the combined flight. In addition, savvy travlers could search the aggregator... and then go book the individual flights directly on the travel sites (you couldn't do this with GDS flights, at least not back then).
So yes, Expedia's way is better, and the best option in 99% of cases. It'd be great if the airlines would play ball to give consumers what they wanted, but... well, good luck with that.
The startup I co-founded (Adioso - YC W09 [1]) tried to do it, including having discussions with a travel insurance provider about offering "layover protection" - so that if one leg was delayed causing you to miss your onward leg(s), your costs are covered. Kiwi.com does this now.
We worked on it from about 2008 till 2013 then basically gave up, as it was too hard to offer a service that customers could really love and trust. (It wasn't for nought; the technology we developed was valuable, and the company was able to rebrand and pivot and now does important work for airlines to optimise loads and fares [2], though I left when the rebrand/pivot happened).
The thing that makes it hard to do is it's basically impossible to get all the flight inventory, including fares and seat availability, that's complete and up-to-date enough to deliver a service that customers can trust.
The engineering challenge is one thing - solving a multi-dimensional travelling salesman problem (price and distance/duration) highly repetitively - but you can solve that with enough smart engineers and "compute", which ITA did in the early 2000s, and on a smaller scale, our team did a decade later.
But you could build the most beautiful routing engine the universe has ever seen, and still have a user experience that's kind-of garbage because the industry just keeps the flight inventory data so locked down.
These days there are APIs and feeds available from the major distribution platforms - Sabre, Amadeus and Travelport, but it's still not comprehensive. You often still need to negotiate individual agreements with major airlines in order to be able to publish and sell their fares. And even then, many of the low-cost airlines (which are often most of interest to travellers who want to find the cheapest route and deal with self-transfer) are not available through these distributors, and some, like Southwest, have blanket refused to be on 3rd party search sites, only starting to relax that position very recently and only with the dominant platform [3]. Kiwi.com has only recently come to a partnership agreement with Ryanair [4] after being in legal battle with them for years [5]. (I hate the thought of having to be at war with your most important partners).
Others have mentioned Skyscanner, which was always the closest to us in what we were each trying to offer (we talked briefly with them about being acquired by them).
Right from the beginning when we got funded for Adioso, my mind became fixated on the thought "if only you get every single flight in the world loaded into one big graph database, what could you do with it?", but it turned out to be a very big "if".
[1] https://techcrunch.com/2010/08/31/adioso/
[2] https://amadeus.com/en/blog/articles/creating-a-private-resa...
[3] https://www.forbes.com/sites/geoffwhitmore/2024/05/25/southw...
[4] https://media.kiwi.com/company-news/kiwi-com-and-ryanair-ann...
[5] https://www.travolution.com/news/kiwi.com-celebrates-three-w...