# How long does an avionics upgrade take?

Source: https://www.wingmanaerocare.com/answers/how-long-does-an-avionics-upgrade-take (updated 2026-10-16)
Published by Wingman AeroCare, Northern Colorado Regional Airport (KFNL). (970) 292-0719.

**Short answer:** It depends on how much of the panel and wiring changes. As typical industry ranges: a slide-in replacement or ADS-B box often takes a few days; a GPS navigator installation commonly takes one to two weeks and an autopilot two to four weeks; and a full glass panel retrofit often takes several weeks or more. The biggest variables are usually parts availability and the installer's backlog, not the hours of labor.

## Typical downtime by type of upgrade

These are general industry ranges for piston singles and twins. Actual time varies with the aircraft, the existing wiring, the shop's schedule, and parts availability.

| Upgrade | Typical aircraft downtime |
|---|---|
| Plug-and-play unit swap (same tray, same wiring) | 1-2 days |
| ADS-B Out installation (standalone or combined with transponder) | 2-5 days |
| GPS navigator replacement with new wiring | 1-2 weeks |
| Autopilot installation | 2-4 weeks |
| Partial glass upgrade (primary flight display or engine monitor) | 1-3 weeks |
| Full panel retrofit (new panel, displays, audio, autopilot, rewiring) | 4-8 weeks or more |

Add time before the airplane arrives (planning, quoting, ordering) and sometimes time after (flight testing, software configuration, PAPR checks).

## What makes an upgrade take longer?

**Parts lead times.** Popular avionics can be backordered for weeks or months. Many shops will not take the aircraft in until all major components are on hand, which is the best way to avoid an airplane sitting half-disassembled.

**Approval paperwork.** Most modern avionics are installed under a supplemental type certificate (STC) with an approved model list (AML) that covers many aircraft types. When an installation is a major alteration, a Form 337 is required, and an IA or other authorized person must approve the aircraft for return to service. Unusual combinations that fall outside an existing STC can require additional approval and add significant time.

**Panel fabrication.** A new panel layout often means a custom-cut panel, new labels, and rewiring. Older aircraft can have decades of abandoned wiring to remove.

**Required tests after the install.** Avionics work commonly triggers recurring-check requirements:

- If the static system is opened, it must be retested before IFR flight in controlled airspace (14 CFR 91.411(a)(2)).
- After installation or maintenance on a transponder where a data correspondence error could be introduced, the integrated system must be tested (14 CFR 91.413(b)).
- ADS-B installations should be verified with an FAA Public ADS-B Performance Report after a test flight.

**Discoveries.** Removing the panel often exposes things that were not visible before: chafed wires, corrosion, or old modifications without paperwork. Each needs a decision before the work can proceed.

**Weight and balance and documentation.** Updated weight and balance, equipment list, and flight manual supplements must be completed before the aircraft returns to service.

## How do I keep downtime short?

- **Plan the whole panel at once.** Doing ADS-B this year and a navigator next year often means pulling the panel twice.
- **Bundle with the annual.** If the panel is coming apart anyway, coordinate inspection timing to minimize total downtime.
- **Confirm parts before drop-off.** Ask your installer whether all major components are in stock before you schedule.
- **Decide on options up front.** Mid-project changes are one of the most common causes of delay.
- **Ask about the test and paperwork plan.** Know who is doing the pitot-static and transponder checks and when.

## How Wingman handles it

At Wingman AeroCare, major avionics installs go to vetted partner shops, and Wingman manages the project so you have one point of contact. Avionics troubleshooting and pitot-static, transponder, and ELT compliance coordination are handled in-house at Northern Colorado Regional Airport (KFNL). If you want to time an upgrade around your annual, or need help planning a panel, call (970) 292-0719 or see [avionics upgrades](https://www.wingmanaerocare.com/services/avionics-upgrades).