Upgrading an old King Air

Upgrading an old King Air


Bringing an old King Air up to date with the first Garmin G1000 retro-fit in Europe

Avionics systems are upgraded far faster than aircraft, which makes retrofits so common. And one of the most common in recent years has been the installation of the Garmin G1000 system into King Airs.

Hundreds have now been completed, with Elliott Aviation in the US completing over 100 and dominating the scene (watch out for a cool film soon showing exactly how it’s done!) but outside the US, the knowledge pool is less deep.

The first in Europe was carried out by UK-based maintenance specialists IAE at Cranfield Aerodrome, on a 1983 King Air, and was such an extensive overhaul that director and avionics specialists Garry Joyce said: “It’s better to think of it as a completely new aircraft. From an avionics point-of-view, it is.”


It took four months from start to finish (speeded up in subsequent conversions) and the total bill was in the region of $350,000. Garry walked us through it.

“We’ve didn’t splice into the old wiring loom at all. It was all brand new wiring. The US company that held the STC (Supplemental Type Certificate) said, ‘Just chop it all out and make a clean start’. There are about 10 wires of the old system that are needed and it’s easier to wire them into a new loom.”

And we’re not just talking about the wiring behind the new panel either. The aircraft was  re-wired from front to back – even the servos for the brakes were new. As Garry said, it’s not necessarily the kind of avionics fit that an operator using the aircraft regularly might want to do because of the downtime, let alone the cost.

However, if the aircraft is ‘in-between owners’ or coming up for sale, then it makes a lot of sense. The book price between a G1000-equipped King Air and a standard analogue aircraft is about $400,000 so the margin isn’t great. But, a King Air with a G1000 is hugely less than a brand new King Air fitted with a Proline glass cockpit – and in Garry’s opinion, the G1000 has more ability. “Half to two-thirds of the price and a better aircraft,” is how he summed it up.

This particular King Air is operated by the Pakistan Air Force for the country’s Intelligence Services so it’s on ‘Secret Squirrel’ missions some of the time. There’s little on the outside, or inside for that matter, to give away its ownership and role.

The King Air arrived at IAE’s hangar at Cranfield after its old autopilot started to play up and become unreliable. No replacement parts or suitable autopilots were available to make a straight swap so the choices were limited – either change the aircraft or retrofit the G1000 with its built-in Garmin GFC 700 digital three-axis ‘fail passive’ autopilot.

Garmin says the GFC 700 is capable of using all data available to G1000, enabling it to maintain airspeed references and optimise performance over the entire envelope. We’ve flown behind the G1000 and GFC 700 fitted to a Cirrus SR22 and can confirm it’s
a marvellous piece of kit, integrating smoothly with the G1000 and its Flight Management System.

Since the PAF and its pilots liked the King Air, they opted for the upgrade, with a new leather interior to boot. That was installed by another UK specialist, Aircraft Interiors, based at Elstree. Six main cabin leather seats, three more in the back, lovely light beige carpet and matching headlining, new cabinetry and woodwork… makes you wonder how it’ll get on with earthy military types inside!

The most obvious elements of the Garmin conversion are the three huge displays on the panel: a central 15-inch Multi Function Display (MFD) with 10.4in Primary Flight Displays (PFDs) either side, plus three standby analogue primary instruments. A keyboard for the Flight Management System, two audio panels, a new Circuit Breaker (CB) panel overhead lights are the other visible bits of new kit. The GFC 700 auto-pilot and many other components (weather radar, transponder, GPS) are built-in.

Remote items in the nose are the dual integrated solid-state Attitude and Heading Reference Systems (AHRS), and dual integrated RVSM-capable digital air data computers. It all weighs considerably less than the analogue instrumentation and auto-pilot that it replaced. Garry said it was the lightest King Air he’d ever weighed. Of course, the aircraft’s weight & balance figures had to be recalculated.

The new displays fit into a brand new top part of the instrument panel, looking very clean and modern. It’s a slightly odd mix of modern and early 1980s classic Beechcraft, with the iconic Beechcraft yokes, power levers and huge trimwheel, and the wonderful classic car-like DV quarterlights.

But it all works superbly. The PFDs are equipped with Garmin’s Synthetic Vision Technology (SVT) which gives a 3D view of what’s ahead – once used, you’d never go back to standard.