A retired soldier told me he used to know people who smuggled jewelries, hard drugs, guns and even people from middle eastern countries to Europe, specifically, Germany! Via planes! In fact, he said some goods were too valuable for them to "risk it" by land transports.

He also added that the aircraft were operated by experienced World War II pilots who specialized in flying at high speed in very low altitudes to make deliveries for infantry units on distress, making them unnoticed on radars and unstoppable for air defense systems.

Are similar methods still possible to this date? if not, what has changed?

similar: How do people smuggle stuff with private airplanes?

NOTE: I have researched myself and so far couldn't find evidence that any sort of actual "improvements" were done in these 70+ years in this matter, it seems the security tightens only when it's demanded and new technologies are not consecutively being used to monitor the skies.

no duplicate of Can someone actually "fly under the radar"? (read comments)

  • 2
    $\begingroup$ Does this answer your question? Can someone actually "fly under the radar"? $\endgroup$ Apr 5, 2020 at 14:28
  • $\begingroup$ @J.Hougaard I've read nearly all the references mentioned in that question. However i'm more or less looking for how they counter these illegal transfers in all these years of advancement in technology, not necessarily how some fly under the radars. $\endgroup$
    – INF
    Apr 5, 2020 at 14:38
  • $\begingroup$ Does this answer your question? How do people smuggle stuff with private airplanes? $\endgroup$
    – Ralph J
    Apr 5, 2020 at 21:55
  • $\begingroup$ @RalphJ, i'm the writer of that question. I restructured it to prevent misinterpretations and no it doesn't answer my question. $\endgroup$
    – INF
    Apr 5, 2020 at 22:46
  • $\begingroup$ you should explain in few simple words why this is not a dupe INSIDE the question. comments can be moved to chat and/or deleted easily. $\endgroup$
    – Manu H
    Apr 14, 2020 at 4:58

1 Answer 1


Yes, it is possible to fly "under the radar".

The type of radio waves that are used by radar and similar equipment to track aircraft generally travel in straight lines. This means that, because of the curvature of the Earth, radars have blind spots at low altitudes when you are sufficiently far from the radar. See the top illustration (not to scale):

enter image description here

While radar coverage today is no doubt much better than it was during World War II, much airborne surveillance today (SSR, ADS, etc.) relies on cooperative targets - which means that tracking an aircraft is a two way communication; the radar sends out a request, and the aircraft replies. The pilot could easily turn off airborne surveillance equipment, thus becoming invisible to secondary radars, ADS and so on, but would still be visible on primary radars, which work by sending out a radio pulse which is reflected off the surface of an aircraft. My point is, primary radar coverage is limited, with more and more primary radars being phased out and replaced by secondary radars, so there are definitely plenty of areas where, if you fly low enough, you can avoid radar detection.

  • $\begingroup$ I only noticed the possible duplicate question after answering $\endgroup$ Apr 5, 2020 at 14:30
  • $\begingroup$ Thanks for your answer, so basically if they don't implement the whole planet with some technology like TARS and rely on these primary equipments, people can still fly unnoticed in the skies. $\endgroup$
    – INF
    Apr 5, 2020 at 14:41
  • $\begingroup$ Could you also explain your point on "relies on cooperative targets"? isn't not cooperating a ticket to being escorted by some fighter aircrafts in a few minutes!? $\endgroup$
    – INF
    Apr 5, 2020 at 14:49
  • $\begingroup$ @INF By “cooperative targets” he’s referring to the target having a transponder that “cooperates” with the radar station by returning a signal of its own. $\endgroup$
    – TomMcW
    Apr 5, 2020 at 22:13
  • $\begingroup$ Could do to elaborate on "clutter", since that's a problem even for air-based radar such as AWACS. $\endgroup$
    – pjc50
    Apr 6, 2020 at 10:01

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