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A friend of the family lives in the approach path of Frankfurt a.M. Airport (FRA, EDDF). Until a few years ago, Tupolev Tu-154s were still flying to this airport, although as I understand, they don't anymore due to noise issues. I could not find out when exactly the last Tu-154 flew to Frankfurt, but the newest photos on Wikimedia Commons are from 2012.
The friend told us that the Tupolevs flying over his town always looked like they were about to fall out of the sky the next minute, because they were somehow flying in an aerodynamically unfavourable configuration, probably due to the aforementioned noise issues.

I find this hard to believe, since from what I have read, the Tu-154 should be more aerodynamically "forgiving" than other planes. For example, to compare the newest variant, the Tu-154M, with a Boeing 737 MAX:

Tu-154 Boeing 737 MAX
wing area 202 m² 127 m²
maximum takeoff weight (MTOW) 104 t 89 t
thrust 103 kN * 3 = 309 kN 130 kN * 2 = 260 kN

Source Tupolev-154 Source 737 MAX

Now the MTOW of the Tupolev is a bit higher than the 737, but with that much thrust and wing area it should generate more lift than the 737. The Wikipedia page also states the Tu-154 was designed for short runways and harsh conditions. That plane can land on a 700 m runway. All this considered it should be able to fly into a nice big-city airport easily.
Unless however the thrust was limited (e.g. for noise reduction).

So now I'm wondering:
Would regulatory or technical conditions force the Tu-154 to fly in an unfavourable or unusual configuration when flying into Frankfurt? Or is our friend wrong?
Information or experiences from other airports and other countries are also welcome.

I have found a video of a Tu-154 landing at Frankfurt, but it only shows the "last few meters" and does not look unusual to me:

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    $\begingroup$ See page 10, the noise fees (NEF) are the highest for Tu-154, 4x the B737-800 $\endgroup$
    – mins
    Oct 4, 2021 at 20:12
  • $\begingroup$ I'm no expert, but that looked like a pretty nice and "normal" landing to me. $\endgroup$
    – FreeMan
    Oct 5, 2021 at 16:05

2 Answers 2

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Your friend is wrong.

The Tu-154 is one of the safest Soviet designs and certainly was not about to fall out of the sky when departing Frankfurt. However, it is indeed a noisy airplane and in order to minimize its noise impact would try to climb more steeply. The flight speeds for steepest climb is only three quarters of the speed for best climb, so it might seem that the Tupolev was flying more slowly when compared to more modern types with larger bypass ratio engines. This might look to the untrained eye like a stall being imminent, but that impression is plain wrong.

During approach the engines would run near idle speed, so noise would be less important. Now I have to speculate what made the Tu-154 look so different. Its large wing area and large flaps give it a very low approach and landing speed - might it be that also during approach your friend judged the airplane to be too slow?

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    $\begingroup$ And it was also a pretty comfortable ride (apart from the noise, but that wasn't too different from contemporary western aircraft like the 727 or Trident). Overall not a bad aircraft at all, and had it not been for the east-west rivalry may well have been much more successful on the international market. $\endgroup$
    – jwenting
    Oct 5, 2021 at 5:57
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    $\begingroup$ Also its engine bay free pure wings are more performant than engine mounted wings. This certainly help with better tolerance to low speed. $\endgroup$
    – Léa Gris
    Oct 5, 2021 at 8:16
  • $\begingroup$ This, and in addition they probably also performed steeper descents than standard 3° for the same reasons. $\endgroup$
    – Robb
    Oct 5, 2021 at 12:51
  • $\begingroup$ So it performs a similar takeoff as jets do at John Wayne Airport (KSNA)? $\endgroup$
    – gparyani
    Oct 5, 2021 at 19:27
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    $\begingroup$ I would be surprised if they flew anything but a standard 3° approach path. The airspace is complicated enough already with everyone on standards, isn't t? $\endgroup$
    – Cpt Reynolds
    Oct 5, 2021 at 19:34
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Given the speculative nature of this question I dare to speculate myself :)

With DC-9s part of the solution to reduce noise during approach was to ban use of full flaps. This was done to reduce drag which in turn reduces required engine power and noise.

The result of lower flap setting is that higher nose-up attitude is required. If similar procedure was applied to Tu-154s, with its large wing sweep angle, it can give an impression of very high nose-up attitude when looking from below.

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  • $\begingroup$ Sounds very credible. +1 $\endgroup$
    – Peter Kämpf
    Oct 6, 2021 at 17:14
  • $\begingroup$ That sounds reasonable. If anyone can produce a media report or, even better, technical guideline of some sort, I will accept this answer. $\endgroup$
    – RobbIZ
    Mar 18, 2022 at 17:01

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