For one, a source from the Syrian military said they had no idea that an Israeli aircraft was anywhere near the Aleppo Governorate, let alone, inside of Syria.
Two, Israel has not officially taken responsibility for the attack on Syria's Aleppo Governorate, despite some hints by Israeli Prime Minister Benjamin Netanyahu.
"Iran is constantly trying to place in Syria precision long-range missile [sic] that are very advanced and highly lethal missiles. We are not prepared to accept this. Our activity against Iran's attempt to establish military bases in Syria and to place advanced weapons there continues all the time", he said, as quoted by the Reuters News Agency.
However, a few days after the attack, some photos were released showing the aftermath of the Israeli bombing on the Sheikh Najjar District of Aleppo city.
GBU-39 Bomb
Based on one of the photos released, the Israeli Air Force used a GBU-39 small diameter bomb, which is not necessarily out of the norm for them, but it does provide some insight into what aircraft might have been used during the attack.
© You NewsThe remains of a GBU-39 small diameter bomb that was used on the night of the Israeli attack on the Aleppo Governorate
F-35 Stealth Jet
According to the South Front publication, "the GBU-39 SBD is a (110 kg) precision-guided glide bomb designed by the US to provide aircraft with the ability to carry a higher number of more accurate bombs. The GBU-39 SBD can be used against stationary targets such as ammo depots, bunkers, etc. The GBU-53 SDB II is upgrated (SIC) for gaining an ability of striking mobile targets."
The South Front highlighted the issues with using one of Israel's more common aircraft like the F-15 and F-16:
"However, the problem is that the GBU-39 SBD's max operational range is 110 km and even a bit more. This can be done by an aircraft flying on a high speed and altitude. Such an aircraft will be an easy target for the Syrian Air Defense Forces' long-range air-defense systems, such as S-200 air defense systems."
This is an important detail because it would require Israel to use a stealth jet, like an F-35, to evade detection by the Syrian air defense units.
Other Theory
Some other observers have reported that the Israeli Air Force may have used an alternative route to bomb Aleppo, rather than their typical route from the Golan Heights.
The Israeli Air Force certainly could have entered Syria via the Latakia Governorate, which is located along the western coast of the country.
When the Israeli Air Force bombed western Syria on the night of September 17th, 2018, they entered the country from the Mediterranean Sea.
However, this incident also caused many problems for Israel as a Russian IL-20 reconnaissance aircraft was mistakenly shot down by the Syrian air defense forces.
Russia would later blame the Israeli Air Force for using the IL-20 as cover during their operation along the Syrian coast.
If F-35s were used, they flew in international waters and launched cruise missiles.
R.C.