Comparison

Cost Index vs ACN/PCN Calculator

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Cost Index

This app helps airline and corporate aircraft operators achieve significant operational savings by calculating the optimum cruise speed for flights based on pilot-inputted conditions and aircraft-specific data. It offers advanced features for cost, fuel, and time optimization, including level change analysis and turbulence margin adjustments.

Highlights
  • Optimum cruise speed calculation
  • Customizable operational data display
  • Minimum fuel burn speed for long range
  • Turbulence margin adjustment
  • Level change analysis for climb/descent decisions
  • Automated data updates
Features
Read full description

Cost Index is an app designed and developed by airline pilots, for airline and corporate aircraft operators. It enables, and has been proven to achieve, significant operational savings. Cruise flight conditions are input by the pilot, then complex algorithms calculate an exact cruise speed which will result in the minimum possible cost for a flight. i.e the optimum cost. Calculations are performed using a tailored aircraft specific data model and customer specific operational costs. Pilots can vary flight level, wind, temperature, weight, and sector cruise distance to find the optimum indicated airspeed and/or mach number. Time difference between optimum cruise speed and minimum time speed can be displayed. Pilots can modify the optimum speed either directly or by decreasing/increasing the time difference. This functionality allows a speed to be selected that will achieve an on-time arrival should this be an overriding factor in the operation. Information displayed on the "Cruise Speed" and "Detail" pages can be customised for the operator. There are over 150 parameters that can be displayed on either of these pages, which can be constructed so that crew do not see any sensitive operational data. As an operational planning/costing tool, all parameters can be made available within the administrator account. For sector lengths approaching the maximum operating range of the aircraft type, a speed for minimum fuel burn is calculated. This speed is better than long range cruise as it takes into account the wind component. When the app detects buffet margin data, a turbulence button is displayed that increases the buffet margin from 1.3g to 1.6g if selected ON. "Level Change" provides unique functionality to aid crew when deciding whether to climb or descend for operational reasons such as turbulence or strong headwinds. There are two features. The first displays the difference in total costs, fuel burn and time, for each flight level when compared to the selected flight level (all other variables the same). The second feature displays the wind required at each level to break even with total cost when compared to the selected level. The flight level with optimum total cost, which is usually the highest achievable level, is highlighted in black with green text. "Downloads" gives the ability to force data updates, although the app will attempt to update it's operational data once it becomes 24 hours old. The number of days since the last update is displayed on the "Downloads" tab badge and also the app icon badge to remind pilots to update the data whilst on the ground. The page has a message area which can display text entered by the administrator. It could be used to promote a flight efficiency programme by giving crews feedback / updates on real savings achieved and tips on new efficient operating techniques. The "Settings" tab is only available to administrator accounts. Its use is for updating operating costs but also includes some customisation functionality. For demonstration purposes, the app has four downloadable sample data sets which contain fictitious data. The following devices are supported: iPad, iPad Retina, iPhone, iPhone Retina 3.5-inch, iPhone Retina 4-inch and iPod Touch. To setup an account for your operational fleet, please contact Flight Efficiency Limited. For more information email: help@flightefficiency.co.uk

About

ACN/PCN Calculator

This app calculates aircraft pavement classification numbers (PCN) and aircraft classification numbers (ACN) to assess airport pavement strength. It helps pilots and aviation professionals ensure safe operations by verifying aircraft weight limitations on runways, taxiways, and aprons.

Highlights
  • ACN/PCN calculation
  • Pavement strength evaluation
  • Aircraft weight verification
  • ICAO ACN/PCN method
  • Comprehensive aircraft database
  • User-friendly interface
Features
Read full description

ACN/PCN Calculator The Ultimate Pavement Strength Tool for Aviation Professionals The ACN/PCN Calculator is your go-to app for evaluating the bearing strength of airport pavements, designed specifically for pilots, flight operations engineers, dispatchers, and airport operators. Whether you’re dealing with flexible or rigid pavements, this app ensures precise calculations to verify safe operations on runways, taxiways, and aprons. By leveraging the ICAO ACN/PCN method, as outlined in Annex 14 and Document 9157 Part 3, the calculator simplifies complex computations, helping you determine the maximum allowable aircraft weight with confidence. Why Choose the ACN/PCN Calculator? • Comprehensive Aircraft Database: Data is sourced from manufacturers’ publications, including the Aircraft Characteristics for Airport Planning (ACAP) manuals. Where necessary, ICAO-recommended methods or alternative sources ensure accuracy. • User-Friendly Design: Optimized for iPhone 8+ screens and fully compatible with iPads, the interface is intuitive and easy to navigate. Supported Aircraft Models Our extensive database includes popular aircraft from leading manufacturers: A300BeK/B4/B4-600R, A319, A320, A321, A330 (all variants), A340 (all variants), A350 (all variants), A380. B727-200, B737 (all variants), B747-400 (all variants), B747-8/F, B757-200/300, B767 (all variants), B777 (including ER/LR/F variants), B787 (all variants). DHC-8-Q400, Global Express/XRS, G5000, G6000, G7500, CRJ series (100-1000), LearJet (31A/ER, 40, 45, 60/XR), Challenger (300, 350, 604, 605). Cessna Citation II, Bravo, S/II, Encore/Encore+, Jet 3/4, Latitude, Sovereign/Sovereign+, Citation X/XLS+. E170, E195, EMB-120/135, Praetor 600, Phenom 300. G650/ER, G600, G550, G500, G450, G400, G280, G200, GVII-G500/600. An-12, An-124-100/M. ATR 42, ATR 72. Convair CV-580/5800. Falcon: 7X, 50/50EX, 900 (all versions), 2000/2000EX. IL-76T/TD. Beechjet 400 series, Hawker 400XP. Request Additional Aircraft: if you don’t see your aircraft listed, use the Feedback button in the Info tab to request additions.  Aircraft data is regularly updated to meet user needs.

Screenshots

Cost Index4 screens
ACN/PCN Calculator4 screens

Verdict

The call

The clearest difference is in-app purchases: Cost Index at none against ACN/PCN Calculator's 10. Cost Index also leads on rating (5.0 vs 4.6) and iOS requirement (8.0 vs 17.6). ACN/PCN Calculator's advantage is update cadence (every 2 months vs every 16 months) and ratings volume (144 vs 1). On price, ads and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. ACN/PCN Calculator sells 10 one-off in-app purchases. Cost Index asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Cost Index holds the better App Store score, 5.0 against 4.6. That said, the two scores are not equally well evidenced: ACN/PCN Calculator has 144 ratings behind it against 1, so its average is the more settled of the two.

UpkeepUpdate frequency

Cost Index ships an update every 16 months, ACN/PCN Calculator every 2 months. The most recent releases landed on November 1, 2026 and November 6, 2026 respectively.

Scorecard6 real differences · 4 level
Cost Index versus ACN/PCN Calculator: the parameters behind the verdict, then further details
ParameterCost IndexACN/PCN Calculator
PriceFreeFree
Rating5.0 (1 ratings) — better4.6 (144 ratings)
Positive reviews—45.5% of reviews
Number of ratings1144 — better
Update frequencyEvery 16 monthsEvery 2 months — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS8.0 — better17.6
Further details — not scored
Size3 MB4 MB
Age rating4+4+
DeveloperFlight Efficiency LimitedAeroKitPro LLC

Customer experience

Cost Index

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

ACN/PCN Calculator

All ratings142 ratings
Positive90.1%
Neutral1.4%
Negative8.5%
Written reviews22 reviews
Positive45.5%
Neutral9.1%
Negative45.5%

In-app purchases

None

Cost Index

No in-app purchases

10 purchases

ACN/PCN Calculator

One-time10
  • G600 (41.7t)Free
  • G650 (45.3t)$4.99
  • Global 5000 GVFD (42.0t)$4.99
Show 7 more
  • Global 6000 (45.2t)$4.99
  • G650ER (47.1t)$4.99
  • G550 (41.4t)$4.99
  • G450 (33.7t)$4.99
  • G280 (18.0t)$4.99
  • Global 7500 (52.2t)$4.99
  • FALCON 7X (31.8t)$4.99

Questions

Is Cost Index free?
Cost Index is free to download, with no in-app purchases.
Is ACN/PCN Calculator free?
ACN/PCN Calculator is free to download, with in-app purchases available.
Which has better reviews, Cost Index or ACN/PCN Calculator?
Cost Index is rated higher. Cost Index averages 5.0 out of 5 from 1 ratings, while ACN/PCN Calculator averages 4.6 from 144 ratings.
Do Cost Index or ACN/PCN Calculator have ads?
Neither Cost Index nor ACN/PCN Calculator shows ads.
Which is updated more often, Cost Index or ACN/PCN Calculator?
Cost Index ships an update every 16 months, and ACN/PCN Calculator every 2 months. Most recently, Cost Index was updated on November 1, 2026 and ACN/PCN Calculator on November 6, 2026.

Other comparisons