Is my savings calculation correct?

[Alberto]

I have a bunch of Fokker 70 and I want to replace them with... Fokker 120NG!

They are in the same fleet group. There are routes served with my Fokker 70 which have demand of, well, around 70pax/day. I am thinking that it would still be profitable to put a Fokker 120NG on these routes. Here is my reasoning:

One Fokker 70 uses 2350kg/hr of fuel (2020nm range); one Fokker 120NG uses 2030kg/hr (2090nm range). Thus I save around 300kg/hr of fuel. Let's say, conservatively, that they fly 10 hours per day. This means 3000kg/day of fuel. At current fuel prices, that's 3000*650/1000=1950$/day saved.

On the other hand, a Fokker 120NG requires one more crew member than a Fokker 70. I currently employ 4929 crew members and they cost me 25'040'561$/month, which comes at roughly 5100$/month. Let's assume conservatively that (because of personal rotation or whatnot), 1 Fokker 70 crew member corresponds to 2 Fokker 120NG crew members. This is still me spending around 10'000$/month more. Let's (again, conservatively) that these are 28-days months, this is around 360$/day in additional expenses.

So, I pay $360/day more, but I save 1950$/day (under very conservative assumptions). Of course the fuel price can increase, but personnel costs also increase, so I think this reasoning could be valid for years to come. On top of this, I get to annoy my competition on these routes, as I now offer more seats. Or I could even capture more demand and, on top of reduced costs, I would also have increased revenue.

It should be a no-brainer and I should switch, right? Or... am I missing something?

[schro]

There's a few more variables that are difficult to calculate -

1. Fuel burn rate is not constant, it's just an average for some particular usage scenario. There's climb/cruise/decent modeled in actual burn, so short routes will be very similar fuel burn between the two and long routes you'll see a difference.

2. As the mtow of a plane goes up, more staff are requiewe across the board, not just cabin crew, but that's subject to rounding and such.

3. Passenger traffic should continue to grow, therefore, the ability to sell 75-80 seats on the 120ngs is quite fantastic.

4. Maintenance costs increase as planes age - brand new ngs will cost a bunch less to maintain than 20 year old 70s.

Overall, your analysis is close enough for hand grenades - cost per trip on either plane is close to the same, but the revenue potential is 70% higher in the ng. Also double check cargo capacity between the two.

[Amelie090904]

Yes, pretty much a no brainer. Less fuel and higher capacity speak for themselves. Then again, yes, a bit more staff and a bit more airport fees etc due to the higher mtow. But nothing you wouldnt save with less fuel consumption and more passengers carried.

The F120 is a fantastic plane and is often overlooked.

[knobbygb]

Your reasoning makes perfect sense.  This is why a/c such as the Max7 (and maybe the 737-700 before it) and the A319Neo are virtually irrelevant in real life. The cost savings just aren't there versus flying with a few empty seats and the possible future growth that brings.  In the game I rarely bother with smaller variants of narrow-bodies now. Real-life mirrors this.

One thing you might like to consider is this:  Do you really need Fokker70 commonality?  Will you keep those around too or totally replace them?  The newer generation offerings in this size class (Embraer 195 or, later, A220) are superior in every sense. The 195 is a little smaller than the F100NG but the E2 addresses that later and it sounds like you don't really need the capacity - yet.  There's a reason the 120NG was never built (well, probably quite a few reasons) - one being that even KLM, the most staunch Fokker-supporter, was not going to buy them and even replaced their F70 with Embraers.

The Fokker also carries a lot less belly cargo than the other options - around 330kg verses 1000kg for the E195-E2 and over 4300kg for the A220!  Cargo revenue is not-insignificant and much overlooked in this game imo. 

Both the newer designs are also faster than the Fokker which makes re-scheduling a non-issue and gives chance to be even more efficient. You can fly more routes overall but, more importantly, the higher speed means you burn around 7% less fuel in cruise, ABOVE and beyond what you calculated due to lower fuel burn itself.

[DanDan]

One thing you might like to consider is this:  Do you really need Fokker70 commonality?  Will you keep those around too or totally replace them?  The newer generation offerings in this size class (Embraer 195 or, later, A220) are superior in every sense.

i agree on the E195. take care about the A220 - it is similar to the E195 IRL, but in AWS it is "large", which makes it a lot more pricey (while it has some advantages too though).

[Alberto]

I agree with your analysis about Embraers. For me the main advantage of swapping to Fokker 120NG is that:

(1) I can just reschedule everything and don't have to bother about adjusting the schedules... given how few "quality of (player's) life" features this game has, I'd rather spare myself rescheduling to a different a/c class using the current interface. Add to this that I like to schedule aircraft (>95% of them, at least) in only two ways: either 7-day scheduling with many many flown hours; or with a daily schedule, in which case they fly 24hours minus 5 hours for A check minus the minimum turnaround time before the A-check. For example, if my Fokker departs at 05:00, it will be back at 23:25; on Sat, add 35min min-turnaround, and it can go into maintenance 00:00-05:00. To be sure that ALL (or the very vast majority) of aircraft uses the maximum allowed time in the air, I use a mathematical optimisation model. (It is a pain, but it allows me to maintain 15.9h of average flight hours even with the majority of routes being short-hauls.) Changing fleet type means I have to re-evaluate the flight time on all the routes, re-run my model, and re-schedule everything almost from scratch. I have no real-life time to do that.

(2) I can keep the newer F70's I had in my fleet and use them to expand to smaller airports without introducing a fourth fleet type (Martin Airways is having a bad time with me opening to both his Prague and Bratislava bases, while he isn't managing to be annoying at my Budapest).

(3) Almost no one wants Fokkers, so I have most production slots to myself! :-)

[knobbygb]

That all sounds good, and I apologise for not realising the A220 was 'Large'. Commonality and instant transfer of schedules sure saves a lot of time!  I've always meant to try the 120NG as I used to use the basic F100 a lot in earlier games, but I haven't got around to it yet.

Just thinking about your point (1) above, don't forget that the A-Check is only weekly so you don't really need to leave that space from midnight to 5am EVERY night. 15.9hrs average usage isn't particularly good (although not terrible).  I'd be aiming for around 17hrs on an a/c that's capable of overnight red-eyes.  With a high RI and CI, don't be afraid of arriving back at base after midnight - it does much less harm than a departure at that time.