I am currently doing a research for my final assignment, about Fractional Aircraft Ownership(FAO). If anybody's curious, yes, I'm widhie's junior (she posted 2 years ago on the similar-but-different-perpective topic).
Currently I'm working on the financial/economical side of the FAO. Here's some points about the topic I'm working on :
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- We got ourselves two aircraft or more that is bought with money from many people, not just one person.
- The people who bought this planes together have the right to use the planes ASAP.
Now the "ASAP" here means that if there's a case of the one of the owners (Mr.X) said "I want to fly in 3 hours!", then the FMC (Fractional Management Company, the one who runs and maintain the aircraft) have to provide the plane at all cost, either with the plane owned by Mr. X (and his partners), other aircraft in the FMC's inventory, and the last resort is to charter an aircraft from another company (very expensive).
- The number of flight hours per year that an owner can use is limited to the share he bought. According to the earlier research, it is between 1/16 (about 50hrs) and 3/8 (about 300hrs).
- The financial and economic calculations in this final assigment are limited to revenue analysis (profit the FMC get from selling the share to the owners -- this would yield annual revenue), and cost analysis (Direct and Indirect Operating Cost).
These calculations would be grouped to ownership cost, Management Monthly Fee, and Occupied Hourly Fee.
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Now, the objective of the simulation is this :
The simulation should be able to give a result on how many planes needed by the FMC, according to shares available.
So basically the user would have to input the number of shares (e.g., Owner 1 : 1/16 share, Owner 2 : 1/8 share, Owner 3 : 5/16 share -- it'd add up to a (1) full share). The end result should be how many planes needed to serve the demand available from the owners.
Assumptions :
- The more share the owner got, the more likely he'd use his share (to fly)*
- Only one type of aircraft.
- Only one destination X (instead of multiple destinations). I'd like to keep it as simple as possible first. Then if it's possible, then i'd upper the ante.
- Doesn't really involve the aspect of crew flight hours etc (if you're in the aviation industry, you'd know that there are limitations on how long pilot and crew are allowed to fly at a time). I'd use a time space of 24 hrs and 1 hour time step.
I currently need help on some few aspects :
- Do I convert the share to flight hours first, or do I let it stay as "share", so I can use it as a fraction (that effects the possibility of the owner to use their share)?
- Do I really have to use many variables to illustrate different owners and/or share, or can I use one variable with commands in it? I haven't really get the grip of using "if-then", because I haven't learn it from the Road Map -- see below.
- How to model the chance of owners using his share in the duration of 24hrs? And to convert it into the "needed number of aircraft"?
FYI,
- I'm using Vensim DSS.
- I'm reading MIT's Road Map - A Guide to Learning System Dynamics. So basically I'm reading and doing the exercise. But not much luck with the effort to make "perfect" models in the exercises
- I'm attaching my veeeery rough and horrible model for all of you to laugh..er, look at.
Thank you for any answers. All helps are greatly appreciated! And sorry for my bad English, it's not my mother tongue
*It's similar to the principal in the MIT Road Map 5 - 4 Generic Structures S-shaped Growth 1.pdf - p13 :
"The probability of a healthy person coming into contact with a sick person is proportional to the total number of sick people in the population. Therefore, the more sick people in the population the greater the chance of coming into contact with one."
So the more share the owner got the greater the chance of him using it.
[Edited on 10-12-2009 by toukairin]