Two men putting on the dome of an aircraft antenna as part of demodification outlined by IAMA

IAMA shines a spotlight on IFC demodification complexity


What happens to an inflight connectivity system when an aircraft is returned to its lessor or transferred to a new operator? What needs to be done to demodify the modification to the aircraft’s type certificate — often via a supplemental type certificate, or STC — back to the premodification state?

It’s an increasingly hot topic given the generational upgrades to inflight connectivity that are underway, and with the background of a shifting ownership and operating picture driven by COVID-19 fleet changes.

Runway Girl Network sat down with Lindsey Sander, technical alliance manager at IAMA, the Independent Aircraft Modifier Alliance, to learn more about what the organisation is doing to simplify and streamline the process.

At one end of the spectrum, some STCs will almost universally be left installed when an aircraft transitions ownership or is returned to the lessor.

“For instance, ADS-B modifications,” says Sander, “will always be valuable, and that’s not necessarily something you want to demodify no matter who Operator B is going to be, because now we have to have ADS-B installed.”

But other aircraft will need to be demodified — in other words, removing an STC installation — to varying levels. Take the example of a satcom IFC installation. At the most basic, it could be simply doing a hard rewiring or changing a program pin to remove a function, all the way up to removing a radome.

From the aircraft owner perspective, Sander says, “generally speaking, when we’re talking about radomes, they like to have the radomes removed completely.”

The question is, then: do you fill the remaining hole with a cover plate “or do we need to replace the skin panel altogether”?

Two men on the ground in an aircraft hanger working on a part.

What happens when IFC radomes need to be uninstalled? Image: Lufthansa Technik

As a rule, when removing a radome it’s cheaper and more efficient to use a cover plate, following the structural repair manual. But in what Sander calls “more of an extreme case” some owners’ leaseback conditions do require the aircraft to be returned in a fully type certified condition, with a fully replaced skin panel.

At the other end of the spectrum, Operator A may have a connectivity system or radome installed that matches Operator B’s needs, so it can be retained on the aircraft.

Top view of workers on the exterior of a Lufthansa aircraft.

Sometimes, the next operator is happy to use a system already installed. Image: Lufthansa Technik

But all of this needs to be discussed and agreed — ideally before the work starts.

“More often than I’d like to admit,” Sander says wryly, “we’ve been in a position where we’ve been in the prototype phase, and nobody has discussed return to service.”

The consequence: unnecessarily last-minute work, which is less comfortable than planning it all out properly.

A man examining a part in a parts facility warehouse.

Ensuring that everyone is on the same plate about when and how systems are installed and removed is vital. Image: Lufthansa Technik

To fix it, first of all IAMA is raising awareness of the issue, including via briefings and a white paper available to its members, with abstracts available publicly. But it’s also doing some critical standards work to enable shared understanding and expectations through the creation of what it calls de-modification levels:

  • Level 1: Deactivate a function
  • Level 2: Complete de-modification without additional modification/repair
  • Level 3: Complete de-modification with additional modification/repair

This allows owners and operators to have a common vocabulary when it comes to leaseback conditions: “we’ll accept a level 1 demodification for system XYZ”, in essence.


The levels enable this shared understanding at the point of the request for proposal, through the preliminary and critical design reviews, technical coordination meetings, and throughout the STC lifecycle.

“So far, we’ve gotten a lot of good feedback” from the industry, Sander says, highlighting that owners and operators are finding that “it’s helpful to see you know, the the perspective of the design organisations and the perspective of the operators just to make sure that everybody’s on the same page.”

The next step for this workstream is to review the white paper in IAMA’s educational platform, while also updating the IAMA Rulebook to ensure that demodification is more frequently discussed throughout the STC lifecycle.

An aircraft that has been gutted exposing inner parts as part of demodification outlined by IAMA.

IAMA’s demodification levels help to improve a shared understanding of the work required. Image: Lufthansa Technik

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All images credited to Lufthansa Technik