Q400 Performance Calculator Support

Takeoff, landing, cruise & missed-approach performance for the DHC-8-402 (Q400)

Need help? I typically respond within 48 hours.

Frequently Asked Questions

What aircraft does this app support?

The app is built specifically for the Bombardier DHC-8-402 (Q400). All performance data, V-speeds, and limit codes are derived from the aircraft's Flight Manual tables.

Is this approved for operational use?

The app is a planning aid intended to speed up performance calculations. Every result must be cross-checked against the approved Aircraft Flight Manual and your operator's procedures. The pilot in command remains responsible for all final decisions.

Does the app work offline?

Yes. All calculations and the airport/runway database run entirely on your device. No internet connection is required to use the app.

How does the subscription and free trial work?

The app includes a 7-day free trial, after which it is $5/month or $30/year. The trial and billing are handled by Apple through your Apple ID. You can cancel anytime in Settings > your Apple ID > Subscriptions before the trial ends to avoid charges.

How do I restore my purchase?

If you reinstall the app or switch devices, open the paywall and tap "Restore Purchases." Make sure you are signed in with the same Apple ID used for the original purchase.

What calculations are included?

Takeoff (V1/VR/V2, max weights, limit codes, reduced/assumed-temperature, MEL and contaminated runway conditions), landing (Vref, Vtarget, Vmax, go-around), cruise (LRC, ISC, HSC, MCR, single-engine, holding), and missed-approach climb gradients — with de-icing/icing speed corrections.

Is my data private?

Yes. The app collects no personal data, has no analytics or tracking, and sends nothing to any server. See the Privacy Policy for details.

I found a value that looks wrong — what should I do?

Please email us with the exact inputs (airport, runway, weight, OAT, wind, configuration) and the result you saw. Accuracy is our top priority and we investigate every report promptly.