QCalc Q400 UTILITIES
Fuel Gross Error Check
Instructions

Enter the fuel uplifted, the fuel remaining from the previous flight, and the reported fuel on board from the FMS. Hit Check Fuel to check the uplifted plus remaining fuel against the FMS's reported amount. Choose the Settings tab to change the default units, gross error threshold, and specific gravity for your fuel type.

KG

KG
KG
Expected On Board
Aircraft Reported
Variance
Variance %
History
Descent Step
Instructions

Enter the IAF altitude. Assumes a descent from 20,000 ft to the IAF altitude on a 3° glide path. Hit Calculate Step to get the nearest whole-mile step point on the descent profile — the altitude you should cross at a rounded distance from the IAF. Change the default start altitude or glide slope on the Settings tab, or override the glide slope below for a single calculation.

°
FT
History
Landing Distance — Normal
Instructions

Enter the Landing Distance Available and the Unfactored Landing Distance already corrected for wind and slope. Choose the runway type and configuration below, then hit Calculate to get the factored Landing Distance Required and the margin against the runway available.

M
M
Available
Unfactored
Required
Margin
History
Landing Distance — Abnormal
Instructions

Enter the Landing Distance Available, the Unfactored Landing Distance already corrected for wind and slope, and the abnormal configuration factor from the AFM. Choose the applicable operational correction, then hit Calculate to get the landing distance required and margin, both with and without the standard operational factor applied.

M
M
If the operational factor can not be accommodated a diversion to an airport with a longer runway must be the first consideration. Landing without the normal safety margins must only be conducted if it can be justified against the risks associated with a diversion.
Required
Margin
With Operational Factor
Required
Margin
History
Fuel
Uplifted Fuel Unit
Remaining Fuel Unit
Aircraft Reported Unit
Gross Error Threshold
Allowable fuel variance (%)
Specific Gravity
For volume ↔ weight conversions
Descent
Start Altitude
Cruise altitude descent begins from
Glide Slope
Descent angle (degrees)
Appearance
Theme
Auto follows your device setting
About

QCalc — Q Calculator
Aviation calculation tool for airliner operations.

All results are for reference only. Always cross-check with approved documentation and procedures.

Changelog
v2.0 July 2026
  • Tab bar now collapses into a hamburger menu on narrow screens where the tabs no longer fit on one line
  • New Abnormal landing distance calculation on the Landing Distance tab
  • New Landing Distance tab with a Normal landing distance calculation
  • New light mode for weird people who like the big light
  • Added override to descent page in case 3° isn't desirable or for single-approach overrides.
v1.4 June 2026
  • New Descent tab calculates the rounded step altitude/distance for an IAF on a 3° glide path
  • Configurable start altitude and glide slope in Settings
v1.3 June 2026
  • Show volume and weight of fuel when uplifting multiple amounts
v1.2 May 2026
  • Multiple uplifted fuel entries with Add more button (up to 5)
  • Remove button on each additional uplift entry
v1.1 Apr 2026
  • Calculation history (last 10 results) on the Fuel Check tab
  • Fixed history incorrectly appearing on the Settings tab
  • Conversion hint now shows uplifted fuel in remaining-fuel units
v1.0 Apr 2026
  • Initial release — fuel gross error check calculator
  • Configurable units: KG, LBS, L, USG, IMP
  • Configurable gross error threshold and specific gravity
  • Equation breakdown shown with each result