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Author Topic: Changing Small Aircraft Type  (Read 557 times)

Offline maya666

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Changing Small Aircraft Type
« on: October 30, 2013, 09:32:13 AM »
Hi,

I've got a hard decision to make. I currently fly a fleet of 21 Emb 110C aircraft (mixed owned and leased). However some of them are getting quite old.
I am now looking to replace them. This could be with new EMB 110PA - Bit less fuel per hour and 2 seats more. Or it could be the Fairchild Metroliner IIIA, also more seats. However the fuel per hour is also around 100kg higher then current, It does fly much faster and a shorter turnaround time.
I am just not sure if it would be worth the extra fuel cost for the faster flight time. Could anyone help with some thoughts about this?

Thank you!

Offline Sanabas

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Re: Changing Small Aircraft Type
« Reply #1 on: October 30, 2013, 10:04:58 AM »
To get a rough estimate, just plug some numbers into a calculator.

Say it's a 500NM route. The E110 will take 500/220 = 2.27 hours, and burn 2.27*190 = 432 kg of fuel. The Metro will take 1.82 hours, burn 582kg of fuel. So to fly the same routes, the EMB will use roughly 75% of the Metro's fuel. Might be a bit better/worse depending on which one is better at landing/takeoff.

However, both will use very little fuel. Look at your income statement now, what's your fuel bill per week? What's your revenue/profit per week? Add 1/3 to your fuel bill, and how much difference will it actually make to your bottom line?

Being faster, and having a 10 minute faster turn (25 vs 35 min) at each end will probably offset most of that. On one 500 NM return trip, you're saving ~1:15 with the metro. On a pair of 250 NM returns, you're saving ~1:35. So fly 4 250 NM return trips with one plane, and you save ~3:10, enough for an extra 100-150 NM return flight. So you'll save on staff, save on plane leasing costs, etc.

Either plane should be fine, and the quicker flights & shorter turns should balance out the extra fuel. If you prefer the extra range/extra seats, take the Metro. If you don't need those things, and the E110 is much cheaper to lease/maintain, take it. Or just toss a coin.  :P

Online LotusAirways

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Re: Changing Small Aircraft Type
« Reply #2 on: October 30, 2013, 12:48:23 PM »
Hi Maya and Sanabas,
Just to add more detail to Sanaba's reply, it is fundamental to understand that speed/distance varies a lot with small and long distances. Let me explain with an example:

1) 240 kts TAS. This means the plane can fly 240 NM in one hour, and since 240 NM divided by 60 minutes equals 4, then the plane flies 4 NM per minute.

2) Now look at a short route, for instance 75 NM distance. You would expect the plane to cover the distance in 19 minutes because 75 NM / 4 NM per minute = 19 minutes of flying. The reality is more like 40 minutes. Both in game and in real life. Now use the 40 minutes trip time and multiply by 4 NM, which equals 160 NM --this is the optimum distance the plane can travel in 40 minutes. Finally, divide the travelled 75 NM by the optimum distance of 160 NM, it equals 0.47. The efficiency is 0.47.

3) Move on to a medium route, for instance 500 NM. You would expect the plane to cover the distance in 500 NM / 4 NM per minute, a 125 minutes flight. The reality is more like 155 minutes. As above, 155 minutes multiplied by 4 NM equals 620 NM. Divide 500 NM by 620 NM, it gives an efficiency of 0.81. 

4) Try a longer route, 700 NM. Again, the expectation is 700 NM / 4 NM per minute, 175 minutes flight. Reality, 190 minutes. Do as above. Efficiency: 0.92.

Hope it is clear.
LA 

Offline Mr.HP

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Re: Changing Small Aircraft Type
« Reply #3 on: October 30, 2013, 01:14:41 PM »
Sanabas's using real flying time, whereas the time show in creating routes take taxiing into account. I'm not sure if taxiing costs fuel in AWS or not  :P

Offline Sanabas

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Re: Changing Small Aircraft Type
« Reply #4 on: October 30, 2013, 01:26:23 PM »
Sanabas's using real flying time, whereas the time show in creating routes take taxiing into account. I'm not sure if taxiing costs fuel in AWS or not  :P

I'm ignoring climb/descent, too. It's just a rough number to compare two planes at cruising speed, using both speed and fuel burn instead of the more common view of looking solely at fuel burn. And yeah, the shorter the route is, the less accurate the comparison will be, because the more time you spend on climb/descent. If you mouseover the flight time in route planning, you'll see both taxi & flying time listed, and flying time will be a little more than you'd expect from just speed/distance. The game takes it into account, but there's no obvious way to see which planes are better at it, other than to use different planes on the same routes and keep really detailed notes, which is far, far more effort than I can be bothered with. I just figure if the specs are similar enough, I'll pick based on other reasons (aesthetics, airline theme, availability, declarations that it's impossible, etc) and assume whichever plane I'm using will make money.  :laugh:
« Last Edit: October 30, 2013, 01:28:59 PM by Sanabas »

Online LotusAirways

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Re: Changing Small Aircraft Type
« Reply #5 on: October 30, 2013, 05:33:53 PM »
HI HP and Sanabas,
Yes, taxing and climbing/descending makes the difference.

Dear Maya,
I had a quick look at your airline. You have several routes with 2 and 3 flights per day using the Embraer 17 seater. Since demand will continue to grow, why not go to the next level and replace the more or less 20 seaters by 40 seaters to cover those routes and more? Have a look at the F27 Mk500 and Mk600 (extra range) which is easily available in both used and new markets. The main specs are:

Seats: 48 (44 in standard seating... recommended)
Range: 870 NM (950 NM in standard seating) for the Mk500, 1150 NM for the Mk600 with 40 standard seats
Speed: 220 kts TAS
Turn-around: 25 + 20 = 45 minutes
Fuel burn: 640 Kg/h
Annual maintenance cost: 3 112 USD * 130.05 = around 404 716 USD
C check duration: 10 days 
Crew: Pilots 2, Cabin crew 1

Then you can add some new routes. For instance, only on the range 621 NM to 950 NM:

Underserved
- SDF-DFW, MIA, TPA...
No competition:
- HOU, AUS, SAT, RSW, PBI, DAL, BDL... 

And probably some others under 620 NM, and from 951 to 1150. Just look for them.
Good luck!

LA

Offline maya666

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Re: Changing Small Aircraft Type
« Reply #6 on: October 31, 2013, 08:53:15 AM »
Thanks for all the advice's yet.
Currently the profit is around 400.000 to 500.000, with a fuel of 430.000.
I mostly serve routes with a demand of 15 pax with the EMB, so I would assume that coming in with a 40pax aircraft would be a bit to much? I could however also transition from the BAC 475 and 500 to Fokkers or something. Would require a bit more planes (speed and seats). I could put the fokker in on the higher demand routes currently served by EMB.

Online LotusAirways

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Re: Changing Small Aircraft Type
« Reply #7 on: October 31, 2013, 10:36:10 AM »
Hi Maya,
It is up to you. An educated guess would be something like:

F27
minimum demand of 15 pax until 200 NM (you will lose money on these at first, but demand will increase with time)
min. dem. 20 pax until 300 NM (should breakeven)
min. dem. 30 pax until 500 NM
min. dem. 40 pax until 800 NM
maximum dem. up to 79, maximum distance 950 NM

BAC500
min. dem. 80 pax below 950 NM (instead of sending 2 F27's)
min. dem. 50 pax above 951 NM

LA
« Last Edit: October 31, 2013, 11:38:55 AM by LotusAirways »

 

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