Aerospace & Defense Manufacturers are Purchasing Obsolete Parts

The Aerospace & Defense industry works with incredibly long product lifecycles that often span decades. These designs use a frozen bill of materials that relies on legacy silicon. New data from Supplyframe’s Commodity IQ platforms shows that these materials are being consumed at rates higher than anything we’ve seen in the last five years. 

What happens when this supply runs out? How will this industry navigate such a scenario? Join us as we take a deeper look at the data, and what A&D manufacturers should do next. 

March Data Reveals Strange Sourcing Patterns 

By the numbers, March 2026 tells a strange story. At first glance, sourcing activity increased by: 

•  85% year-over-year in the memory category
• Diodes saw a 53% increase
• Logic went up 49%
• Transistors went up 48%
• Amplifier circuits increased by 42%

Across all these categories, parts are constrained, with lead times between 30-50 weeks. Some of this sourcing demand can also be explained by the recent geopolitical shifts that are necessitating full production of A&D assets.  

If we zoom in further, the single fastest-moving part MPN around the globe was ST Microelectronics’ LM324QT. This is a quad op-amp, with an original design that dates back to 1972, making it older than most engineers who are buying it. 

Between ST, onsemi, and Texas Instruments, three variants of the LM324 occupied five out of the ten sourcing slots with year-over-year sourcing activity growth as high as 5,075%. So, in essence, A&D manufacturers are buying historical amounts of 1972 silicon, which presents potential obsolescence and lifecycle risks. 

This is nothing new: A&D programs are known to carry multi-decade lifespans, but what happens when a program needs to be requalified because a part that was widely available back during design is no longer sourceable? 

It can cost over $10M to requalify a program because of component shortages or obsolescence, so this may very quickly become a costly issue. 

How the A&D Sector Fits into These Patterns

Programs designed between 2016 and 2020 are now ramping to full production, and they’re using the parts they chose back then, not the parts engineers would choose today. Here’s how those same commodities we mentioned earlier fit into A&D designs: 

• Memory: Industrial-temperature DDR3 and DDR4 DRAM go into radar signal processors, mission computers, edge computing, and black-box recorders. Industrial NAND and SD cards are flying out of distribution too.
• Diodes: covers everything from 1N4148 switching diodes to TVS arrays to Schottky rectifiers. On an aero or defense board, diodes show up in every power rail, every external interface for electrostatic discharge protection, and every reverse-polarity guard. 
• Logic: This is the glue between everything on a defense board: level translators, interface converters, gates, multiplexers. 
• Transistors: This includes both the small-signal workhorses like onsemi’s MMBT3904LT1G and the wide-bandgap gallium nitride and silicon carbide parts driving radar and directed-energy power stages. 
• Amplifier circuits: This is the LM324 story. Quad op-amps condition signals from pressure sensors, thermocouples, IMU analog fronts, and radar IF stages. 

What Aerospace & Defense Manufacturers Should do Next 

The data here shows that stock levels at authorized distributors are a lagging indicator. Lead times on fast-moving parts are at 30-50 weeks, despite supposedly healthy inventory. The independent market is absorbing the overflow, and the gap between authorized /independent distributors provides an early warning. 

Pre-qualified independents with counterfeit-screening programs need to be on every approved vendor list. No longer a contingency, but a primary source. The good news is that Supplyframe can help with this. 

Our solutions offer alternate parts that match form, fit, and function. The Findchips Blog also explores in-demand parts to help engineers navigate situations like this. 

Take for example the ongoing conversation around LM324 variants, which are one of the most in-demand parts right now, according to our DSI Network.

In the case of the LM324 variants, the strongest alternative right now is the LM2902 in SOIC 14. This part is pin compatible with the LM324 and carries a wider operating temperature range. Buyers who can tolerate a JFET input should evaluate the TL074 next, and those who need a tighter offset should use the LM324A. 

If you’re struggling with DRAM, shift to HBM designs and lock in allocation. 

The bottom line is this: the parts that are being panic-sourced today are the parts your engineers will need to design out tomorrow. Stay ahead of the curve and look to the future now, so you’re not caught off-guard when the last-time-buy notices start going out. 

Learn more about how Supplyframe helps A&D Manufacturers stay ahead of trends like this at Supplyframe.com.