Helicopter Hover Density Altitude Checker
Check density altitude against your helicopter's IGE and OGE hover ceilings — the rotorcraft version of the go/no-go performance check.
Helicopter hover charts are published against density altitude and gross weight. Look up your IGE/OGE ceilings at today's weight, then compare them with the LZ's density altitude here.
Formula
⚠️ For flight planning and education only — always verify against your aircraft's POH/AFM, official weather sources and certified instruments. Not for primary navigation or airworthiness decisions.
Check density altitude against your helicopter's IGE and OGE hover ceilings — the rotorcraft version of the go/no-go performance check.
About Helicopter Hover Density Altitude Checker
For helicopter pilots, density altitude is not about runway length — it is about whether the machine can hover at all. This checker computes the density altitude at your landing zone and compares it directly against the in-ground-effect (HIGE) and out-of-ground-effect (HOGE) hover ceilings you read from the performance charts at today's gross weight, returning the margin in feet for each.
How to use Helicopter Hover Density Altitude Checker
- 1Enter — sensible defaults are pre-filled so you see a worked result immediately.
- 2Read the live results: .
- 3Check the "With your numbers" line to see the formula DA = PA + 118.8 × (OAT − ISA); margin = hover ceiling − DA substituted step by step.
- 4Adjust inputs (or flip the unit toggle) until the scenario matches yours, then copy or share the result.
Why use Helicopter Hover Density Altitude Checker?
- ✓Instant, free and private — every calculation runs in your browser, nothing is uploaded
- ✓Built on the published formula DA = PA + 118.8 × (OAT − ISA); margin = hover ceiling − DA with sources cited on the page
- ✓Helicopter hover charts are published against density altitude and gross weight. Look up your IGE/OGE ceilings at today's weight, then compare them with the LZ's density altitude here.
- ✓Switch units, tweak any input and watch every result update live
Frequently asked questions
What is the difference between HIGE and HOGE?+
Hovering in ground effect rides on a cushion of air within roughly one rotor diameter of the surface, demanding noticeably less power. Out of ground effect — over water, trees, or during vertical reference work — that cushion vanishes. HOGE ceilings are therefore always lower, and confined-area operations should be planned against HOGE, not HIGE.
Where do I find my hover ceilings?+
In the performance section of the rotorcraft flight manual: the 'Hover Ceiling IGE' and 'Hover Ceiling OGE' charts. Enter with your gross weight and read the maximum density altitude. Those two numbers, at today's weight, are what you type into this tool.
Why does a mountain LZ feel fine in the morning but marginal at 2 pm?+
Temperature. A 15 °C swing changes density altitude by roughly 1,800 ft. A pinnacle that offered comfortable HOGE margin at dawn can sit above your HOGE ceiling by mid-afternoon at the same weight — the classic trap behind many mountain-rescue power-margin incidents.
Can I trade fuel for hover margin?+
Yes — weight is the lever you control. Hover ceilings rise steeply as gross weight falls, so burning down or defueling a few hundred pounds can buy thousands of feet of ceiling. Recompute the chart at the lighter weight and re-check the margin here before committing to an OGE approach.
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