STEP 0: Pre-Calculation Summary
Formula Used
Minimum Design Index = ((Cost Index*Cost Priority (%))+(Weight Index*Weight Priority (%))+(Period Index*Period Priority (%)))/100
DImin = ((CI*Pc)+(WI*Pw)+(TI*Pt))/100
This formula uses 7 Variables
Variables Used
Minimum Design Index - Minimum Design Index is a comparable quantity in conceptual design phase which considers Cost, Weight and Time period indices.
Cost Index - Cost index is the summation of all the contributors in cost configuration parameters. The cost configuration parameters are valued on the scale of 0-10 (best=10 and worst=0).
Cost Priority (%) - Cost Priority (%) is a factor which shows the priority of cost objective on a percentage scale. It is oriented according to the user's definition of priorities.
Weight Index - Weight index is the summation of all the contributors in weight configuration parameters. The weight configuration parameters are valued on the scale of 0-10 (best=10 and worst=0).
Weight Priority (%) - Weight Priority (%) is a factor which shows the priority of Weight factor on a percentage scale. It is oriented according to the user's definition of priorities.
Period Index - Period Index is the summation of all the contributors in period configuration parameters. The Period configuration parameters are valued on the scale of 0-10 (best=10 and worst=0).
Period Priority (%) - Period Priority (%) is a factor which shows the priority of Time factor of on a percentage scale. It is oriented according to the user's definition of priorities.
STEP 1: Convert Input(s) to Base Unit
Cost Index: 55 --> No Conversion Required
Cost Priority (%): 10 --> No Conversion Required
Weight Index: 50 --> No Conversion Required
Weight Priority (%): 15.1 --> No Conversion Required
Period Index: 95 --> No Conversion Required
Period Priority (%): 19 --> No Conversion Required
STEP 2: Evaluate Formula
Substituting Input Values in Formula
DImin = ((CI*Pc)+(WI*Pw)+(TI*Pt))/100 --> ((55*10)+(50*15.1)+(95*19))/100
Evaluating ... ...
DImin = 31.1
STEP 3: Convert Result to Output's Unit
31.1 --> No Conversion Required
(Calculation completed in 00.000 seconds)
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## Credits

Created by Vedant Chitte
All India Shri Shivaji Memorials Society's ,College of Engineering (AISSMS COE PUNE), Pune
Vedant Chitte has created this Calculator and 25+ more calculators!
Verified by Anshika Arya
National Institute Of Technology (NIT), Hamirpur
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Cost Priority (%) = ((Minimum Design Index*100)-(Weight Index*Weight Priority (%))-(Period Index*Period Priority (%)))/Cost Index Go
Period Priority (%) = ((Minimum Design Index*100)-(Weight Index*Weight Priority (%))-(Cost Index*Cost Priority (%)))/Period Index Go
Period Index = ((Minimum Design Index*100)-(Weight Index*Weight Priority (%))-(Cost Index*Cost Priority (%)))/Period Priority (%) Go
Cost Index = ((Minimum Design Index*100)-(Weight Index*Weight Priority (%))-(Period Index*Period Priority (%)))/Cost Priority (%) Go
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Minimum Design Index = ((Cost Index*Cost Priority (%))+(Weight Index*Weight Priority (%))+(Period Index*Period Priority (%)))/100
DImin = ((CI*Pc)+(WI*Pw)+(TI*Pt))/100

## What is Conceptual Design of Aircraft ?

While doing the Conceptual Design phase a designer makes a lots of conceptual models and compare them to select the best conceptual design. For this he compares the model on the basis of various objective like Cost of Aircraft, Weight Of Aircraft, Design Time Period for making that model, Performance Factor, Maintainability Factor, Producibility Factor, Beauty (or Aesthetics) Factor, etc.

The Designer defines Objective index which depends upon the parameters which influence the respective objective. Sum of all of the parameters contributing the objective factor on scale of 1-10 gives objective index. Now this objective index has its own priorities, in a conceptual design model the priorities are shown in percentage.
Now how these factor influence the model is given by the product of the objective index and its priority (taken as a number (conversion from percentage)), it is the share of design index. And if the share of design index is subjected to the Cost, Weight and Design Time only, It is called Minimum Design Index.
As they are common factors in all type of Aircrafts.

Minimum design index calculator uses Minimum Design Index = ((Cost Index*Cost Priority (%))+(Weight Index*Weight Priority (%))+(Period Index*Period Priority (%)))/100 to calculate the Minimum Design Index, The Minimum design index formula is defined as sum of products of objective indices and their respective priorities percentage of Cost, Weight, and Design Time factors whole divided by hundred. Minimum Design Index is denoted by DImin symbol.

How to calculate Minimum design index using this online calculator? To use this online calculator for Minimum design index, enter Cost Index (CI), Cost Priority (%) (Pc), Weight Index (WI), Weight Priority (%) (Pw), Period Index (TI) & Period Priority (%) (Pt) and hit the calculate button. Here is how the Minimum design index calculation can be explained with given input values -> 31.1 = ((55*10)+(50*15.1)+(95*19))/100.

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