I traveled CAI-LHR in J yesterday with onward travel to SJC and the following may help.
1) I stayed at the Le Meridien at Cairo Airport, got up at 5am for the 0530 shuttle and was at the airport at 0535. (BTW, I arrived the previous night from DXB on EK. When you get into the immigration hall, you can take the left or right queue and I would recommend taking the right hand queue as, although they look similar, the fixed metal barriers to route you to the immigration officials are shorter on the right and on getting to the front of the queue was around 25% quicker than taking the left hand queue)
2) Flight leaves at 8am and the previous flight to this from T2 leaves nearly 2 hours previous which results in T2 being empty. No queues or any issue getting past first security checkpoint (but have your passport and itinerary either printed out or on your phone for inspection)
3) As my journey was CAI - LHR - SJC I wanted my bag short checked so I could recover in LHR (LHR - CAI due to arrive LHT at 1210, SJC flight leaves at 1455). The guy at check in was a bit hesitant but went to chat with the manager and it was no problem. All laptops, chargers etc need to be checked and therefore I just had my Bose Headphones and passport, wallet etc as carry on.
3A) I did have a complication with my onward LHR-SJC Boarding pass as I have 2 passports and my Egypt visa is in one and my ESTA is registered for the other. Therefore he was not able to give me by SJC boarding pass which was no issue as I would just sort it out in LHR (see later point)
4) No issue with immigration (empty) and in the "lounge" in about 5 mins. Lounge is pretty cr*p but nice view of the airport and wifi works ok
5) Left the lounge at around 0710 to go to gate E04. 5 min walk to the gate. 2 queues, one for males and one for females. Of course a couple of Egyptian males tried to jump the 20 person long male queue and feign complete surprise when told this was ladies only. The first guy got away with it but I made my displeasure obvious and then told the other guy the back of the queue was that way so off he went (queue jumpers are not my favorite people). My Bose QC15 were inspected and no issue carrying them on however i did have 3 AAA spare batteries for the headphones and he was going to confiscate those before agreeing they were no threat!! The guy in security has a rigid plastic template through which all electronic items (except headphones) must pass. One guy was upset as he had a small square power bank which did not fit and was confiscated. Another woman had a rather bulky old style phone which also did not fit but, after much deliberation was allowed to keep it.
6) Flight left 5 mins late. Food was average (Avoid the salmon starter) and we arrived at 1210
7) No one at immigration in T5 and so waiting for bags at 1225. By 1300 only about 20 bags had come out. By 1310 it said all bags delivered so a few of us query at baggage services and after first saying that was it, then it seemed one container had got lost but was now coming. 1325, bag delivered (and we wonder why everyone hates checking bags)
8) Back up to First wing. Can't give me my BP as ESTA is not associated with my first passport used to checkin in Cairo. Despite swiping 2nd passport - no dice. Anyway, a phone call and about a 5 min wait, all previous passport details removed and new ones put in and it all works (and it definitely helped that I had my ESTA confirmation showing it did not expire until 2018 printed out to prove it was not my issue (ie not having an ESTA). Through first wing in 2 mins, quick shower , drink and back off to B gates. SJC flight pretty good although I notice that on the 789 there is a lot more interference if the guy in the seat behind bangs his foot rest (you can really feel it in your seat).
Summary:
1) Short check no issue in Cairo
2) Don't take anything electronic and over the size limits past check in as it will be taken off you (exception is headphones). This includes power banks.
3) If you have two passports and traveling to the US then probably best to enable them both for ESTA's to avoid my issue
4) Even though I had nearly 3 hours connecting time, 1.5 of that went away with clearing UK immigration, baggage delays and BP delays. No issue but just goes to show how time can disappear quickly
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